Langton's ant: Difference between revisions
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{{task|Cellular automata}}
[[wp:Langton's ant|Langton's ant]] is a cellular automaton that models an [https://en.wikipedia.org/wiki/Ant ant] sitting on a plane of cells, all of which are white initially, the ant facing in one of four directions.
Each cell can either be black or white.
The ant moves according to the color of the cell it is currently sitting in, with the following rules:
::# If the cell is black, it changes to white and the ant turns left;
::# If the cell is white, it changes to black and the ant turns right;
::# The ant then moves forward to the next cell, and repeat from step 1.
<br>This rather simple ruleset leads to an initially chaotic movement pattern, and after about 10000 steps, a cycle appears where the ant moves steadily away from the starting location in a diagonal corridor about 10 cells wide.
Conceptually the ant can then walk infinitely far away.
;Task:
Start the ant near the center of a 100<small>x</small>100 field of cells, which is about big enough to contain the initial chaotic part of the movement.
Follow the movement rules for the ant, terminate when it moves out of the region, and show the cell colors it leaves behind.
The problem has received some analysis; for more details, please take a look at the Wikipedia article (a link is below)..
;See also:
* Wikipedia: [https://en.wikipedia.org/wiki/Langton%27s_ant Langton's ant].
;Related task:
* [[Conway%27s_Game_of_Life|Conway's Game of Life]].
* [[Elementary_cellular_automaton|Elementary cellular automaton]]
<br><br>
=={{header|11l}}==
{{trans|Python}}
<syntaxhighlight lang="11l">T.enum Dir
UP
RIGHT
DOWN
LEFT
-V color_WHITE = Char(‘ ’)
-V color_BLACK = Char(‘#’)
F invert_color(&grid, x, y)
‘Invert the color of grid at x, y coordinate.’
I grid[y][x] == :color_BLACK
grid[y][x] = :color_WHITE
E
grid[y][x] = :color_BLACK
F next_direction(grid, x, y, =direction)
‘Compute next direction according to current position and direction.’
V turn_right = grid[y][x] != :color_BLACK
V direction_index = Int(direction)
I turn_right
direction_index = (direction_index + 1) % 4
E
direction_index = (direction_index + 4 - 1) % 4
V directions = [Dir.UP, Dir.RIGHT, Dir.DOWN, Dir.LEFT]
direction = directions[direction_index]
R direction
F next_position(=x, =y, direction)
‘Compute next position according to direction.’
I direction == UP
y--
E I direction == RIGHT
x--
E I direction == DOWN
y++
E I direction == LEFT
x++
R (x, y)
F print_grid(grid)
‘Display grid.’
print(80 * ‘#’)
print(grid.map(row -> row.join(‘’)).join("\n"))
F ant(width, height, max_nb_steps)
‘Langton's ant.’
V grid = [[:color_WHITE] * width] * height
V x = width I/ 2
V y = height I/ 2
V direction = Dir.UP
V i = 0
L i < max_nb_steps & x C 0 .< width & y C 0 .< height
invert_color(&grid, x, y)
direction = next_direction(grid, x, y, direction)
(x, y) = next_position(x, y, direction)
i++
print_grid(grid)
ant(width' 75, height' 52, max_nb_steps' 12000)</syntaxhighlight>
{{out}}
<pre>
################################################################################
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</pre>
=={{header|Action!}}==
<syntaxhighlight lang="action!">DEFINE DIRN="0"
DEFINE DIRE="1"
DEFINE DIRS="2"
DEFINE DIRW="3"
DEFINE BLACK="1"
DEFINE WHITE="2"
DEFINE MAXX="159"
DEFINE MAXY="95"
BYTE FUNC TurnLeft(BYTE dir)
IF dir=DIRN THEN
RETURN (DIRW)
FI
RETURN (dir-1)
BYTE FUNC TurnRight(BYTE dir)
IF dir=DIRW THEN
RETURN (DIRN)
FI
RETURN (dir+1)
PROC DrawAnt(INT x,y)
BYTE c,dir
dir=DIRN
DO
c=Locate(x,y)
IF c=BLACK THEN
Color=WHITE
Plot(x,y)
dir=TurnLeft(dir)
ELSE
Color=BLACK
Plot(x,y)
dir=TurnRight(dir)
FI
IF dir=DIRN THEN
y==-1
IF y<0 THEN EXIT FI
ELSEIF dir=DIRE THEN
x==+1
IF X>MAXX THEN EXIT FI
ELSEIF dir=DIRS THEN
y==+1
IF Y>MAXY THEN EXIT FI
ELSE
x==-1
IF x<0 THEN EXIT FI
FI
OD
RETURN
PROC Main()
BYTE CH=$02FC
BYTE y
Graphics(7+16)
SetColor(0,0,2)
SetColor(1,0,12)
Color=2
FOR y=0 TO MAXY
DO
Plot(0,y) DrawTo(MAXX,y)
OD
DrawAnt(80,48)
DO UNTIL CH#$FF OD
CH=$FF
RETURN</syntaxhighlight>
{{out}}
[https://gitlab.com/amarok8bit/action-rosetta-code/-/raw/master/images/Langton's_ant.png Screenshot from Atari 8-bit computer]
=={{header|Ada}}==
<
procedure Langtons_Ant is
Line 47 ⟶ 264:
begin
loop -- iterate the loop until an exception is raised
if Is_Black(Ant_X, Ant_Y) then
Left(Ant_North, Ant_West);
Line 53 ⟶ 269:
Right(Ant_North, Ant_West);
end if;
Is_Black(Ant_X, Ant_Y) := not Is_Black(Ant_X, Ant_Y);
Ant_X := Ant_X - Ant_North; -- this may raise an exception
Ant_Y := Ant_Y - Ant_West; -- this may raise an exception
Line 68 ⟶ 285:
Ada.Text_IO.Put_Line("# Iteration:" & Integer'Image(Iteration));
end Langtons_Ant;
</syntaxhighlight>
Ouptut (to save space, I have removed the all-blank lines):
<pre style="height:30ex;overflow:scroll"> ## ############ ##
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# Iteration:
</pre>
=={{header|
[[File:ant_phpoFTAAk.png|100px|Output png]]
<syntaxhighlight lang="aime">void
ant(integer x, y, d, list map)
{
while (-1 < x && x < 100 && -1 < y && y < 100) {
integer e, p, w;
data b;
b = map[y];
w = b[x >> 3];
b[x >> 3] = w ^ p;
d += w & p ? 1 : 3;
e = d & 1;
set(e, $e + ((d & 2) - 1) * (2 * e - 1));
}
}
integer
main(void)
{
file f;
list l;
call_n(100, lb_p_data, l, data().run(13, 0));
ant(50, 50, 2, l);
f.create("ant.pbm", 00644).text("P4\n100 100\n");
l.ucall(f_data, 1, f);
0;
}</syntaxhighlight>
=={{header|ALGOL 68}}==
<syntaxhighlight lang="algol68">BEGIN
# size of board for Langton's ant #
INT max board = 100;
[ 1 : max board, 1 : max board ]CHAR board;
# start with the board all white #
CHAR white = " ", black = "#";
FOR r TO 1 UPB board DO FOR c TO 2 UPB board DO board[ r, c ] := white OD OD;
# possible ant directions #
INT head left = 0, head up = 1, head right = 2, head down = 3;
# returns the new direction if we turn left from curr direction #
OP LEFT = ( INT curr direction )INT:
IF curr direction = head left THEN head down
ELIF curr direction = head down THEN head right
ELIF curr direction = head right THEN head up
ELSE head left
FI ; # LEFT #
# returns the new direction if we turn right from curr direction #
OP RIGHT = ( INT curr direction )INT:
IF curr direction = head left THEN head up
ELIF curr direction = head up THEN head right
ELIF curr direction = head right THEN head down
ELSE head left
FI ; # RIGHT #
# move the ant until it leaves the board #
INT ant row := max board OVER 2;
INT ant col := max board OVER 2;
INT ant direction := head up;
INT max row := 1;
INT max col := 1;
INT min row := max board;
INT min col := max board;
INT moves := 0;
WHILE ant row >= 1 LWB board AND ant row <= 1 UPB board
AND ant col >= 2 LWB board AND ant col <= 2 UPB board
DO
moves +:= 1;
IF ant row > max row THEN max row := ant row FI;
IF ant col > max col THEN max col := ant col FI;
IF ant row < min row THEN min row := ant row FI;
IF ant col < min col THEN min col := ant col FI;
IF board[ ant row, ant col ] = white THEN
# ant turns right on a white square #
ant direction := RIGHT ant direction;
board[ ant row, ant col ] := black
ELSE
# ant turns left on a black square #
ant direction := LEFT ant direction;
board[ ant row, ant col ] := white
FI;
# move the ant #
IF ant direction = head up THEN ant row -:= 1
ELIF ant direction = head down THEN ant row +:= 1
ELIF ant direction = head left THEN ant col -:= 1
ELSE # ant direction = head right # ant col +:= 1
FI
OD;
# show resultant position #
print( ( "After ", whole( moves, 0 ), " moves."
, " Showing rows ", whole( min row,0 ), " to ", whole( max row, 0 )
, " columns ", whole( min col,0 ), " to ", whole( max col, 0 )
, newline
)
);
FOR r FROM min row TO max row DO
print( ( board[ r, min col : max col ], newline ) )
OD
END</syntaxhighlight>
{{out}}
<pre>
After 11655 moves. Showing rows 28 to 78 columns 1 to 79
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# ### # # # ##### # ##### # # ## # ## #
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# ### # # # # # ######## # # ## #### #
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# ### # # # # # # ## ## ## ####
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# ### # # # ## #### #### ### ####
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# ### # # ## ## ## ### ## #####
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####
##
</pre>
=={{header|APL}}==
{{works with|Dyalog APL}}
<syntaxhighlight lang="apl">
⍝ initialize a Langton's Ant setup with a grid of size left x right (square by default)
langton ← {
⍝ If rows not specified, set equal to columns
⍺ ← ⍵
⍝ 0=white, 1=black. Start with all white
grid ← ⍺ ⍵ ⍴ 0
⍝ Start the ant in the middle
ant ← 2 ÷⍨ ⍺ ⍵
⍝ Aimed in a random direction
dir ← ?4
⍝ return everything in a tuple
grid ant dir
}
⍝ iterate one step: takes and returns state as created by langton function
step ← {
grid ant dir ← ⍵
⍝ Turn left or right based on grid cell
dir ← 1 + 4|dir+2×grid[⊂ant]
⍝ Toggle cell color
grid[⊂ant] ← 1 - grid[⊂ant]
⍝ Advance along dir. Since coordinates are matrix order (row,col),
⍝ up is -1 0, right is 0 1, down is 1 0, and left is 0 -1
ant +← (4 2 ⍴ ¯1 0, 0 1, 1 0, 0 ¯1)[dir;]
grid ant dir
}
⍝ to watch it run, open the variable pic in the monitor before executing this step
{} { state ∘← ⍵ ⋄ pic ∘← '.⌺'[1+⊃1⌷⍵] ⋄ _←⎕dl ÷200 ⋄ step ⍵} ⍣≡ langton 100</syntaxhighlight>
{{Out}}
The final contents of <tt>pic</tt> (eliding trailing blank lines)
<pre>.......................⌺⌺.⌺.⌺...........................
......................⌺.⌺⌺⌺.⌺⌺.........................
.....................⌺⌺⌺⌺...⌺.⌺.......................
.....................⌺⌺⌺⌺⌺.⌺..⌺⌺......................
......................⌺...⌺⌺.⌺⌺.⌺...................
.......................⌺⌺⌺...⌺..⌺⌺.................
........................⌺...⌺⌺.⌺⌺.⌺...............
.........................⌺⌺⌺...⌺..⌺⌺.............
..........................⌺...⌺⌺.⌺⌺.⌺...........
...........................⌺⌺⌺...⌺..⌺⌺.......
............................⌺...⌺⌺.⌺⌺.⌺.....
.............................⌺⌺⌺...
..............................⌺...⌺⌺.⌺⌺.⌺....
...............................⌺⌺⌺...⌺..⌺⌺.
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....................................⌺⌺...⌺⌺.⌺⌺⌺.⌺⌺⌺⌺..⌺.
....................................⌺⌺.⌺.⌺⌺⌺⌺.....⌺..
...................................⌺⌺⌺⌺.⌺⌺...⌺⌺.⌺⌺⌺⌺..⌺.⌺..⌺..⌺..⌺⌺⌺...
...................................⌺.⌺⌺.⌺⌺⌺..⌺.⌺.⌺⌺.⌺.⌺.....⌺.⌺.....⌺.
.......................................⌺.⌺..⌺....⌺⌺.⌺⌺..⌺.⌺..⌺⌺⌺.
.......................................⌺⌺.⌺....⌺..⌺⌺⌺⌺⌺.⌺....⌺....⌺..⌺.
......................................⌺.⌺⌺.⌺..⌺....⌺⌺.⌺⌺.⌺..⌺⌺⌺......
....................................⌺.⌺...⌺..⌺..⌺..⌺..⌺⌺⌺...⌺⌺..⌺⌺....
...................................⌺⌺⌺.⌺.⌺⌺⌺⌺⌺.⌺⌺⌺⌺⌺⌺.⌺⌺⌺.⌺⌺⌺⌺⌺⌺⌺.⌺.
...................................⌺.⌺.⌺....⌺⌺⌺⌺⌺...⌺⌺..⌺⌺⌺⌺⌺.
.....................................⌺..⌺⌺...⌺......⌺..⌺.⌺⌺..⌺⌺⌺.
..................................⌺⌺⌺⌺...⌺⌺⌺⌺⌺.⌺⌺⌺⌺⌺⌺⌺⌺⌺...⌺.
.............................⌺⌺....⌺..⌺.....⌺⌺⌺.⌺.⌺...⌺.⌺⌺⌺..
............................⌺..⌺..⌺⌺⌺⌺.⌺⌺...⌺⌺⌺.⌺⌺...⌺⌺⌺.⌺⌺.....
...........................⌺⌺⌺....⌺.⌺⌺.⌺.⌺⌺⌺⌺⌺...⌺....⌺..⌺..⌺⌺.
...........................⌺.⌺⌺⌺⌺⌺.⌺.⌺...⌺⌺..⌺⌺.....⌺....⌺...⌺..
...............................⌺⌺⌺⌺⌺⌺.⌺⌺⌺⌺..⌺⌺.⌺...⌺..⌺⌺..⌺.⌺.
.............................⌺⌺......⌺.⌺⌺⌺.⌺⌺..⌺⌺⌺⌺...⌺...
..............................⌺..⌺.⌺⌺⌺⌺⌺..⌺...⌺.⌺⌺...⌺..⌺..
..............................⌺⌺.⌺⌺⌺.⌺⌺⌺⌺⌺⌺⌺.....⌺.....⌺.
.............................⌺.⌺..⌺⌺.⌺⌺......⌺...⌺⌺....
............................⌺..⌺.⌺⌺⌺⌺........⌺⌺⌺..⌺⌺..
............................⌺.⌺⌺.⌺⌺⌺............⌺⌺..
.............................⌺⌺.....................................................................
..............................⌺⌺....................................................................</pre>
=={{header|Applesoft BASIC}}==
{{trans|BBC BASIC}}
<syntaxhighlight lang="gwbasic"> 0 IF T THEN FOR Q = 0 TO T STEP 0: XDRAW T AT X * S,H - Y * S:D = FN M(D + D( PEEK (234)) + F):X = X + X(D):Y = Y + Y(D):Q = X > M OR X < 0 OR Y > M OR Y < 0: NEXT Q: END : DATA 100,50,50,3,220,1,4,-1,1,1,1,-1,-1
1 HGR : SCALE= 1: ROT= 0
2 LET S$ = CHR$ (1) + CHR$ (0) + CHR$ (4) + CHR$ (0) + "5'" + CHR$ (0)
3 POKE 236, PEEK (131): POKE 237, PEEK (132)
4 LET S = PEEK (236) + PEEK (237) * 256 + 1
5 POKE 232, PEEK (S)
6 POKE 233, PEEK (S + 1)
7 READ M,X,Y,S,H,T,F,D(0),D(4),Y(0),X(1),Y(2),X(3)
8 DEF FN M(N) = N - INT (N / F) * F
9 GOTO</syntaxhighlight>
=={{header|AutoHotkey}}==
ahk forum: [http://ahkscript.org/boards/viewtopic.php?f=17&t=1363 discussion]
{{works with|AutoHotkey 1.1}} (Fixed by just me)
<syntaxhighlight lang="autohotkey">#NoEnv
SetBatchLines, -1
; Directions
Directions := {0: "North", 1: "East", 2: "South", 3: "West"}
; Initialize the plane (set all cells to white)
White := 0xFFFFFF
Plane := []
PW := PH := 100
loop, % PH {
I := A_Index
loop, % PW
Plane[I, A_Index] := White
}
; Let it run
DI := D := 0 ; initial direction
X := Y := 50 ; initial coordinates
while (X > 0) && (X <= PW) && (Y > 0) && (Y <= PH) {
D := (D + ((Plane[X, Y] ^= White) ? 1 : 3)) & 3
if (D & 1)
X += -(D = 3) + (D = 1)
else
Y += -(D = 0) + (D = 2)
}
; Show the result
HBM := CreateDIB(Plane, PW, PH, 400, 400, 0)
Gui, Margin, 0, 0
Gui, Add, Text, x0 y0 w20 h440 Center 0x200, W
Gui, Add, Text, x20 y0 w400 h20 Center 0x200, N
Gui, Add, Picture, x20 y20 w400 h400 0x4E hwndHPIC ; SS_REALSIZECONTROL = 0x40 | SS_BITMAP = 0xE
DllCall("User32.dll\SendMessage", "Ptr", HPIC, "UInt", 0x172, "Ptr", 0, "Ptr", HBM) ; STM_SETIMAGE = 0x172
Gui, Add, Text, xp+5 yp h20 0x200 BackgroundTrans, % "Initial direction: " . Directions[DI]
Gui, Add, Text, x20 y420 w400 h20 Center 0x200, S
Gui, Add, Text, x420 y0 w20 h440 Center 0x200, E
Gui, Show, , Langton's ant (%PW%x%PH%)
Return
GuiClose:
ExitApp
CreateDIB(PixelArray, PAW, PAH, BMW := 0, BMH := 0, Gradient := 1) { ; SKAN, 01-Apr-2014 / array version by just me
SLL := (PAW * 3) + (PAW & 1)
VarSetCapacity(BMBITS, SLL * PAH, 0)
P := &BMBITS
loop, % PAH {
R := A_Index
loop, % PAW
P := Numput(PixelArray[R, A_Index], P + 0, "UInt") - 1
P += (PAW & 1)
}
HBM := DllCall("Gdi32.dll\CreateBitmap", "Int", PAW, "Int", PAH, "UInt", 1, "UInt", 24, "Ptr", 0, "UPtr")
HBM := DllCall("User32.dll\CopyImage", "Ptr", HBM, "UInt", 0, "Int", 0, "Int", 0, "UInt", 0x2008, "UPtr")
DllCall( "Gdi32.dll\SetBitmapBits", "Ptr", HBM, "UInt", SLL * PAH, "Ptr", &BMBITS)
if (!Gradient)
HBM := DllCall("User32.dll\CopyImage", "Ptr", HBM, "UInt", 0, "Int", 0, "Int", 0, "Int", 8, "UPtr")
return DllCall("User32.dll\CopyImage", "Ptr", HBM, "UInt", 0, "Int", BMW, "Int", BMH, "UInt", 0x200C, "UPtr")
} ; http://ahkscript.org/boards/viewtopic.php?f=6&t=3203</syntaxhighlight>
=={{header|AutoIt}}==
<syntaxhighlight lang="autoit">
Global $iCountMax = 100000
Global $aFields[100][100][2]
Global $iDelayStep = 10 ; stop between steps in msec
Global $aDirection[4][4] = [ _ ; [ direction 0-3 ][ left change x, y, right change x, y ]
[-1, 0, +1, 0], _ ; == direction 0
[ 0, -1, 0, +1], _ ; == direction 1
[+1, 0, -1, 0], _ ; == direction 2
[ 0, +1, 0, -1]] ; == direction 3
Global $hGui = GUICreate("Langton's ant", 100*8, 100*8)
GUISetBkColor(0xFFFFFF)
For $i = 0 To 99
For $j = 0 To 99
$aFields[$i][$j][0] = GUICtrlCreateLabel('', $j*8, $i*8)
GUICtrlSetColor(-1, 0xFF0000)
$aFields[$i][$j][1] = 0
Next
Next
GUISetState()
GUICtrlSetData($aFields[49][49][0], '#')
Do
Sleep($iDelayStep)
Until Not _SetAnt()
Do
Until GUIGetMsg() = -3
Func _SetAnt()
Local Static $iRowLast = 49, $iColLast = 49, $iCount = 0
Local Static $aCol[2] = [0xFFFFFF,0x000000], $iDirection = 0
Local $iRow, $iCol, $fRight = False
If $iCount = $iCountMax Then Return 0
; == get current color
Local $iLastColor = $aFields[$iRowLast][$iColLast][1]
; == go to left/right
If $iLastColor = 0 Then $fRight = True
; == set the ant to the next field
Local $indexX = 0, $indexY = 1
If $fRight Then
$indexX = 2
$indexY = 3
EndIf
$iRow = $iRowLast + ($aDirection[$iDirection][$indexX])
$iCol = $iColLast + ($aDirection[$iDirection][$indexY])
If $iRow < 0 Or $iRow > 99 Or $iCol < 0 Or $iCol > 99 Then Return 0
GUICtrlSetData($aFields[$iRowLast][$iColLast][0], '')
GUICtrlSetData($aFields[$iRow][$iCol][0], '#')
; == direction for next step
If $fRight Then
$iDirection += 1
If $iDirection = 4 Then $iDirection = 0
Else
$iDirection -= 1
If $iDirection = -1 Then $iDirection = 3
EndIf
; == change the color of the current field
GUICtrlSetBkColor($aFields[$iRowLast][$iColLast][0], $aCol[(Not $iLastColor)*1])
$aFields[$iRowLast][$iColLast][1] = (Not $iLastColor)*1
$iRowLast = $iRow
$iColLast = $iCol
$iCount += 1
WinSetTitle($hGui, '', "Langton's ant [ step: " & StringFormat('%06d', $iCount) & " ]")
Return 1
EndFunc ;==>_SetAnt
</syntaxhighlight>
[http://www.imgbox.de/users/BugFix/langtons_ant.png To see the GUI output, click here.]
--[[User:BugFix|BugFix]] ([[User talk:BugFix|talk]]) 14:48, 16 November 2013 (UTC)
=={{header|AWK}}==
<syntaxhighlight lang="awk">
# usage: awk -v debug=0 -f langton.awk
# Simulates the cellular automaton "Langton's ant",
# see http://en.wikipedia.org/wiki/Langton%27s_ant
function turnRight() {
dir++
if( dir>4 ) { dir=1 }
}
function turnLeft() {
dir--
if( dir<1 ) { dir=4 }
}
function move() {
if (dir==1) { y--; z="^" }
if (dir==3) { y++; z="v" }
if (dir==2) { x++; z=">" }
if (dir==4) { x--; z="<" }
}
function ant() {
if( debug ) AntStat() ##
if( grid[x,y]==0 ) { turnLeft() } else { turnRight() }
if( grid[x,y]==0 ) { color=1 } else { color=0 }
if( debug ) print( "# action", color, dir, z ) ##
grid[x,y] = color
move()
}
###
function AntStat() {
printf( "Move# %d : Ant @ x=%d y=%d dir=%d %s color=%d\n",
moveNr, x,y, dir,z, grid[x,y] )
}
function dumpGrid() {
AntStat()
printf( "Grid:" )
for(xx=1; xx<=limit/10; xx++) {
printf( "....+....%s", xx )
}
printf "\n"
cSum=0
for(yy=1; yy <= limit; yy++) {
printf( "%4d:",yy )
for(xx=1; xx <= limit; xx++) {
c = grid[xx,yy]
if( c ) cSum++
c1++
c2+=grid[xx,yy]
if( (xx==x)&&(yy==y) ) { c=z } # Ant
printf( c )
}
printf( "\n" )
}
printf( "Cells: %d 'black' cells: %d Moves: %d\n\n", limit*limit, cSum, moveNr )
}
BEGIN {
print( "Langton's ant\n" )
limit = 72
for(x=1; x <= limit; x++) {
for(y=1; y <= limit; y++) {
grid[x,y] = 0
}
}
moveNr = 0
x = 36
y = 28
dir = 1 # 1=up/north 2=right/east 3=down/south 4=left/west
z = "!"
while( moveNr < 11200 ) {
moveNr++
ant()
if(x<0 || x>limit) break
if(y<0 || y>limit) break
# Snapshots:
if (moveNr==163 || moveNr==1297 || moveNr==10095 ) dumpGrid()
if (y<=5 ) break
}
dumpGrid()
}
END { print("END.") }
</syntaxhighlight>
=={{header|BBC BASIC}}==
<syntaxhighlight lang="bbc basic">
REM Implementation of Langton's ant for Rosetta Code
fieldsize%=100
Line 269 ⟶ 899:
UNTIL x%>fieldsize% OR x%<0 OR y%>fieldsize% OR y%<0
END
</syntaxhighlight>
=={{header|bc}}==
The output function <code>o</code> prints the resulting image (as a [[wp:Netpbm_format|PBM image]]) to <code>stdout</code>. One can either store it into a file or pipe it through an image viewer (e.g. <code>bc langton.bc | display</code>).
<syntaxhighlight lang="bc">define o() {
auto i, j
"P1 "
w
h
for (j = 0; j < h; j++) {
for (i = 0; i < w; i++) {
a[j * w + i]
}
}
}
define l(w, h, x, y) {
auto a[], d, i, x[], y[]
/* d represents one of the four possible directions:
* 0
* ⇑
* 3⇐ ⇒1
* ⇓
* 2
* The arrays x[] and y[] contain the changes to the x and y direction for
* each value of d.
*/
x[1] = 1
x[3] = -1
y[0] = -1
y[2] = 1
while (1) {
i = y * w + x
if (a[i] == 0) d += 1 /* turn right if white */
if (a[i] == 1) d -= 1 /* turn left if black */
if (d < 0) d = 3
if (d > 3) d = 0
x += x[d]
y += y[d]
a[i] = 1 - a[i] /* toggle cell colour */
if (x < 0) break
if (x == w) break
if (y < 0) break
if (y == h) break
}
o()
}
l(100, 100, 50, 50)
quit</syntaxhighlight>
=={{header|Befunge}}==
<syntaxhighlight lang="befunge">"22222 -"*>>>1-:0\:"P"%\v>\7%1g48*-/2%3*48*+,1+:20g`!v1g01+55p03:_$$$>@
!"$(0@`vp00_^#!:p+7/"P"<<^g+7/*5"p"\%"P"/7::+g03*"d":_$,1+>:40g`!^1g03<
_::10g\v>00g+4%:00p::3\`\1-*50g+50p:2\-\0`*+::0\`\"c"`+50g:0\`\"c"`++#^
-*84g1<v^+1*2g09pg08g07-*g06-1*2p09:%2/g06:gp08:+7/*5"p"\p07:%"P"/7:p06
0p+:7%^>>-:0`!*+10p::20g\-:0`*+20p:"d"*50g::30g\-:0`!*+30p::40g\-:0`*+4</syntaxhighlight>
{{out}}
<pre style="font-size: 4px"> ## ############ ##
# #### # ##
### ## ## #
# # # # # #
## ## # # ### #
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# ### # # # # # ######## # # ## #### #
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# ### # # # ## # # #
### # ## ## ##
# ### # # ##
### # ##
# # # # #
#### ##
# ## #
####
##</pre>
=={{header|BQN}}==
<code>Ant</code> is the main function, which runs the ant simulation given a starting point, direction and grid of zeros.
<code>Fmt</code> then formats into hashes and spaces.
<code>_while_</code> is an idiom from [https://mlochbaum.github.io/bqncrate/ BQNcrate] which helps with conditional looping.
<syntaxhighlight lang="bqn">Rot ← ¬⊸{-⌾(𝕨⊸⊑)⌽𝕩}
Fmt ← ⊏⟜" #"
_while_ ← {𝔽⍟𝔾∘𝔽_𝕣_𝔾∘𝔽⍟𝔾𝕩}
Ant ← 2⊑{ # Generator Block
p‿d‿g:
r ← d Rot˜ p⊑g
⟨
p + r
r
¬⌾(p⊸⊑)g
⟩
} _while_ { # Condition Block
p‿d‿g:
∧´(p≥0‿0)∧p<≢g
}
•Show Fmt Ant ⟨50‿50, 0‿1, 100‿100⥊0⟩</syntaxhighlight>
[https://mlochbaum.github.io/BQN/try.html#code=Um90IOKGkCDCrOKKuHst4oy+KPCdlajiirjiipEp4oy98J2VqX0KRm10IOKGkCDiio/in5wiICMiCl93aGlsZV8g4oaQIHvwnZS94o2f8J2UvuKImPCdlL1f8J2Vo1/wnZS+4oiY8J2UveKNn/CdlL7wnZWpfQoKQW50IOKGkCAy4oqReyAjIEdlbmVyYXRvciBCbG9jawogIHDigL9k4oC/ZzoKICByIOKGkCBkIFJvdMucIHDiipFnCiAg4p+oCiAgICBwICsgcgogICAgcgogICAgwqzijL4ocOKKuOKKkSlnCiAg4p+pCn0gX3doaWxlXyB7ICAgIyBDb25kaXRpb24gQmxvY2sKICBw4oC/ZOKAv2c6CiAg4oinwrQocOKJpTDigL8wKeKIp3A84omiZwp9CgrigKJTaG93IEZtdCBBbnQg4p+oNTDigL81MCwgMOKAvzEsIDEwMOKAvzEwMOKlijDin6k=&norun Try It!] (Running will take some time due to JS, ≈40 secs on my machine)
=={{header|C}}==
Requires ANSI terminal.
<
#include <stdlib.h>
#include <string.h>
Line 347 ⟶ 1,121:
walk();
return 0;
}</
=={{header|C sharp|C#}}==
<
namespace LangtonAnt
Line 383 ⟶ 1,157:
private readonly Direction[] _leftTurn = new[] { Direction.West, Direction.North, Direction.South, Direction.East };
private readonly Direction[] _rightTurn = new[] { Direction.East, Direction.South, Direction.North, Direction.West };
private readonly int[] _xInc = new[] { 0, 1,
private readonly int[] _yInc = new[] {-1, 0, 0,
public Langton(int width, int height, Point origin)
Line 443 ⟶ 1,217:
}
}
</syntaxhighlight>
Output:
<pre>
<Blank lines eliminated for efficiency> # #
## # #
# ### ##
#### ### #
##### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## # ##
### # ## ##
# ## ## ## #
#### ### # # ###
# # # ## #### #
### # # # # ## #
### # ## # ## # ##
# # ## # # ##
# # # ##### # #
# ##### ## ######
### ## # ## # # # ## # ##
## # ####### # # ### ## #
# # ###### ## # # ## # #
# # # ## # ###### ####### #
# #### ## # #### ## ## # ## #
# #### # # ###### ## ###
# # ## # ### # ## ## ###
####### # ## ## # #
#### ## ## #### ## ## ## # #
# # # ### ## ### # #### #
### ### # # ##### # # #
# # ### #### ## # ## ### ## #
## ## #### #### # # # #
# # ## ### ### ### #
## ## ### #### # ### ## #
## # #### # # # ## ### ## #
#### ## ## #### # # # # ### #
# ## ### # # ## # # # # # #
# # # ## ## # # ### ##
## # # ##### # # # # #
# ## # # ## ## # ### ###
# # # # # # ### ## ## #
### # ##### ###### ### ####### # ##
# # # ##### ## ##### #####
# ## # # # ## ### ###
#### ##### ######### # #
## # # ### # # # ### ###
# # #### ## ### ## ### ## ##
### # ## # ##### # # # ## ###
# ##### # # ## ## # # # #
###### #### ## # # ## # # ##
## # ### ## #### # ###
# # ##### # # ## # # #
## ### ####### # # ##
# # ## ## # ## #
# # #### ### ## #
# ## ### ## ##
##
##
</pre>
=={{header|C++}}==
[[File:langtonsAnt_cpp.png|300px]]
If you want to see it running infinitely, set the const bool INFINIT_RUN = true
<syntaxhighlight lang="cpp">
#include <windows.h>
#include <string>
//--------------------------------------------------------------------------------------------------
using namespace std;
//--------------------------------------------------------------------------------------------------
const int BMP_SIZE = 600, CELL_SIZE = 4, GRID_SIZE = BMP_SIZE / CELL_SIZE;
const bool INFINIT_RUN = false;
enum cellState { WHITE, BLACK, ANT };
enum facing { NOR, EAS, SOU, WES };
enum state { RUNNING, RESTING };
//--------------------------------------------------------------------------------------------------
class myBitmap
{
public:
myBitmap() : pen( NULL ) {}
~myBitmap()
{
DeleteObject( pen );
DeleteDC( hdc );
DeleteObject( bmp );
}
bool create( int w, int h )
{
BITMAPINFO bi;
ZeroMemory( &bi, sizeof( bi ) );
bi.bmiHeader.biSize = sizeof( bi.bmiHeader );
bi.bmiHeader.biBitCount = sizeof( DWORD ) * 8;
bi.bmiHeader.biCompression = BI_RGB;
bi.bmiHeader.biPlanes = 1;
bi.bmiHeader.biWidth = w;
bi.bmiHeader.biHeight = -h;
HDC dc = GetDC( GetConsoleWindow() );
bmp = CreateDIBSection( dc, &bi, DIB_RGB_COLORS, &pBits, NULL, 0 );
if( !bmp ) return false;
hdc = CreateCompatibleDC( dc );
SelectObject( hdc, bmp );
ReleaseDC( GetConsoleWindow(), dc );
width = w; height = h;
return true;
}
void clear()
{
ZeroMemory( pBits, width * height * sizeof( DWORD ) );
}
void setPenColor( DWORD clr )
{
if( pen ) DeleteObject( pen );
pen = CreatePen( PS_SOLID, 1, clr );
SelectObject( hdc, pen );
}
void saveBitmap( string path )
{
BITMAPFILEHEADER fileheader;
BITMAPINFO infoheader;
BITMAP bitmap;
DWORD wb;
GetObject( bmp, sizeof( bitmap ), &bitmap );
DWORD* dwpBits = new DWORD[bitmap.bmWidth * bitmap.bmHeight];
ZeroMemory( dwpBits, bitmap.bmWidth * bitmap.bmHeight * sizeof( DWORD ) );
ZeroMemory( &infoheader, sizeof( BITMAPINFO ) );
ZeroMemory( &fileheader, sizeof( BITMAPFILEHEADER ) );
infoheader.bmiHeader.biBitCount = sizeof( DWORD ) * 8;
infoheader.bmiHeader.biCompression = BI_RGB;
infoheader.bmiHeader.biPlanes = 1;
infoheader.bmiHeader.biSize = sizeof( infoheader.bmiHeader );
infoheader.bmiHeader.biHeight = bitmap.bmHeight;
infoheader.bmiHeader.biWidth = bitmap.bmWidth;
infoheader.bmiHeader.biSizeImage = bitmap.bmWidth * bitmap.bmHeight * sizeof( DWORD );
fileheader.bfType = 0x4D42;
fileheader.bfOffBits = sizeof( infoheader.bmiHeader ) + sizeof( BITMAPFILEHEADER );
fileheader.bfSize = fileheader.bfOffBits + infoheader.bmiHeader.biSizeImage;
GetDIBits( hdc, bmp, 0, height, ( LPVOID )dwpBits, &infoheader, DIB_RGB_COLORS );
HANDLE file = CreateFile( path.c_str(), GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL );
WriteFile( file, &fileheader, sizeof( BITMAPFILEHEADER ), &wb, NULL );
WriteFile( file, &infoheader.bmiHeader, sizeof( infoheader.bmiHeader ), &wb, NULL );
WriteFile( file, dwpBits, bitmap.bmWidth * bitmap.bmHeight * 4, &wb, NULL );
CloseHandle( file );
delete [] dwpBits;
}
HDC getDC() const { return hdc; }
int getWidth() const { return width; }
int getHeight() const { return height; }
private:
HBITMAP bmp;
HDC hdc;
HPEN pen;
void *pBits;
int width, height;
};
//--------------------------------------------------------------------------------------------------
class Ant
{
public:
Ant()
{
_bmp.create( BMP_SIZE, BMP_SIZE );
ZeroMemory( _grid, sizeof( _grid ) );
RED_BRUSH = CreateSolidBrush( 255 );
_antState = RUNNING;
}
~Ant()
{
DeleteObject( RED_BRUSH );
}
void setPosition( int x, int y )
{
_sx = x; _sy = y;
_facing = WES;
}
void mainLoop()
{
switch( _antState )
{
case RUNNING:
simulate();
// fall thru
case RESTING:
display();
}
}
void setHWND( HWND hwnd ) { _hwnd = hwnd; }
private:
void simulate()
{
switch( _grid[_sx][_sy] )
{
case BLACK:
_grid[_sx][_sy] = WHITE;
if( --_facing < NOR ) _facing = WES;
break;
case WHITE:
_grid[_sx][_sy] = BLACK;
if( ++_facing > WES ) _facing = NOR;
}
switch( _facing )
{
case NOR:
if( --_sy < 0 )
{
if( INFINIT_RUN ) _sy = GRID_SIZE - 1;
else _antState = RESTING;
}
break;
case EAS:
if( ++_sx >= GRID_SIZE )
{
if( INFINIT_RUN ) _sx = 0;
else _antState = RESTING;
}
break;
case SOU:
if( ++_sy >= GRID_SIZE )
{
if( INFINIT_RUN ) _sy = 0;
else _antState = RESTING;
}
break;
case WES:
if( --_sx < 0 )
{
if( INFINIT_RUN ) _sx = GRID_SIZE - 1;
else _antState = RESTING;
}
}
}
void display()
{
_bmp.clear();
HBRUSH br; RECT rc;
int xx, yy; HDC dc = _bmp.getDC();
for( int y = 0; y < GRID_SIZE; y++ )
for( int x = 0; x < GRID_SIZE; x++ )
{
switch( _grid[x][y] )
{
case BLACK: br = static_cast<HBRUSH>( GetStockObject( BLACK_BRUSH ) ); break;
case WHITE: br = static_cast<HBRUSH>( GetStockObject( WHITE_BRUSH ) );
}
if( x == _sx && y == _sy ) br = RED_BRUSH;
xx = x * CELL_SIZE; yy = y * CELL_SIZE;
SetRect( &rc, xx, yy, xx + CELL_SIZE, yy + CELL_SIZE );
FillRect( dc, &rc, br );
}
HDC wdc = GetDC( _hwnd );
BitBlt( wdc, 0, 0, BMP_SIZE, BMP_SIZE, dc, 0, 0, SRCCOPY );
ReleaseDC( _hwnd, wdc );
}
myBitmap _bmp;
HWND _hwnd;
HBRUSH RED_BRUSH;
BYTE _grid[GRID_SIZE][GRID_SIZE];
int _sx, _sy, _facing;
state _antState;
};
//--------------------------------------------------------------------------------------------------
class wnd
{
public:
int wnd::Run( HINSTANCE hInst )
{
_hInst = hInst;
_hwnd = InitAll();
_ant.setHWND( _hwnd );
_ant.setPosition( GRID_SIZE / 2, GRID_SIZE / 2 );
ShowWindow( _hwnd, SW_SHOW );
UpdateWindow( _hwnd );
MSG msg;
ZeroMemory( &msg, sizeof( msg ) );
while( msg.message != WM_QUIT )
{
if( PeekMessage( &msg, NULL, 0, 0, PM_REMOVE ) != 0 )
{
TranslateMessage( &msg );
DispatchMessage( &msg );
}
else
{
_ant.mainLoop();
}
}
return UnregisterClass( "_LANGTONS_ANT_", _hInst );
}
private:
static int WINAPI wnd::WndProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam )
{
switch( msg )
{
case WM_DESTROY: PostQuitMessage( 0 ); break;
default:
return DefWindowProc( hWnd, msg, wParam, lParam );
}
return 0;
}
HWND InitAll()
{
WNDCLASSEX wcex;
ZeroMemory( &wcex, sizeof( wcex ) );
wcex.cbSize = sizeof( WNDCLASSEX );
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = ( WNDPROC )WndProc;
wcex.hInstance = _hInst;
wcex.hCursor = LoadCursor( NULL, IDC_ARROW );
wcex.hbrBackground = ( HBRUSH )( COLOR_WINDOW + 1 );
wcex.lpszClassName = "_LANGTONS_ANT_";
RegisterClassEx( &wcex );
return CreateWindow( "_LANGTONS_ANT_", ".: Langton's Ant -- PJorente :.", WS_SYSMENU, CW_USEDEFAULT, 0, BMP_SIZE, BMP_SIZE, NULL, NULL, _hInst, NULL );
}
HINSTANCE _hInst;
HWND _hwnd;
Ant _ant;
};
//--------------------------------------------------------------------------------------------------
int APIENTRY _tWinMain( HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow )
{
wnd myWnd;
return myWnd.Run( hInstance );
}
//--------------------------------------------------------------------------------------------------
</syntaxhighlight>
=={{header|Chapel}}==
<syntaxhighlight lang="chapel">
config const gridHeight: int = 100;
config const gridWidth: int = 100;
class PBMWriter {
var imgDomain: domain(2);
var imgData: [imgDomain] int;
proc PBMWriter( height: int, width: int ){
imgDomain = { 1..#height, 1..#width };
}
proc this( i : int, j : int) ref : int{
return this.imgData[ i, j ];
}
proc writeImage( fileName: string ){
var file = open(fileName, iomode.cw);
var writingChannel = file.writer();
writingChannel.write("P1\n", imgDomain.dim(1).size, " " ,imgDomain.dim(2).size,"\n");
for px in imgData {
writingChannel.write( px, " " );
}
writingChannel.write( "\n" );
writingChannel.flush();
writingChannel.close();
}
}
enum Color { white, black };
inline proc nextDirection( position: 2*int, turnLeft: bool ): 2*int {
return ( (if turnLeft then 1 else -1 ) * position[2], (if turnLeft then -1 else 1 ) * position[1] );
}
proc <( left: 2*int, right: 2*int ){
return left[1] < right[1] && left[2] < right[2];
}
proc <=( left: 2*int, right: 2*int ){
return left[1] <= right[1] && left[2] <= right[2];
}
proc main{
const gridDomain: domain(2) = {1..#gridHeight, 1..#gridWidth};
var grid: [gridDomain] Color;
var antPos = ( gridHeight / 2, gridWidth / 2 );
var antDir = (1,0); // start up;
while (0,0) < antPos && antPos <= (gridHeight, gridWidth ) {
var currColor = grid[ antPos ];
grid[antPos] = if currColor == Color.white then Color.black else Color.white ;
antDir = nextDirection( antDir, currColor == Color.black );
antPos = antPos + antDir;
}
var image = new PBMWriter( height = gridHeight, width = gridWidth );
for (i, j) in gridDomain {
image[i,j] = if grid[gridHeight-j+1,gridHeight-i+1] == Color.black then 0 else 1;
}
image.writeImage( "output.png" );
}
</syntaxhighlight>
=={{header|Clojure}}==
In keeping with the spirit of Clojure, this program eschews mutable state entirely. Instead, all computation occurs within a single recursive loop whose "variables" are "adjusted" at each iteration, a natural fit for this particular execution model.
<syntaxhighlight lang="clojure">(let [bounds (set (range 100))
xs [1 0 -1 0] ys [0 -1 0 1]]
(loop [dir 0 x 50 y 50
grid {[x y] false}]
(if (and (bounds x) (bounds y))
(let [cur (not (grid [x y]))
dir (mod (+ dir (if cur -1 1)) 4)]
(recur dir (+ x (xs dir)) (+ y (ys dir))
(merge grid {[x y] cur})))
(doseq [col (range 100)]
(println
(apply str
(map #(if (grid [% col]) \# \.)
(range 100))))))))</syntaxhighlight>
=={{header|COBOL}}==
The following program displays the simulation in the console, and a very small font size (~4pt) will be needed to fit it into the window.
{{works with|OpenCOBOL}}
<syntaxhighlight lang="cobol"> IDENTIFICATION DIVISION.
PROGRAM-ID. langtons-ant.
DATA DIVISION.
WORKING-STORAGE SECTION.
78 Grid-Size VALUE 100.
01 grid-area.
03 grid-x OCCURS Grid-Size TIMES.
05 grid-y OCCURS Grid-Size TIMES.
07 cell-colour PIC X VALUE "W".
88 black VALUE "B".
88 white VALUE "W".
01 ant-x PIC 999.
01 ant-y PIC 999.
01 ant-direction PIC 9.
88 upward VALUE 0.
88 rightward VALUE 1.
88 downward VALUE 2.
88 leftward VALUE 3.
78 Pause-Time-Ns VALUE 10000000.
01 display-y PIC 999.
78 Black-Background VALUE 0.
78 White-Background VALUE 7.
01 i PIC 999.
01 j PIC 999.
01 pause PIC X.
PROCEDURE DIVISION.
main-line.
DIVIDE Grid-Size BY 2 GIVING ant-x, ant-y
PERFORM display-initial-grid
PERFORM UNTIL (ant-x = Grid-Size OR 0)
OR (ant-y = Grid-Size OR 0)
PERFORM step-simulation
CALL "CBL_OC_NANOSLEEP" USING Pause-Time-Ns
END-PERFORM
DISPLAY "Press enter to quit." AT LINE 1 COLUMN 1
ACCEPT pause
GOBACK
.
step-simulation.
IF black (ant-x, ant-y)
SET white (ant-x, ant-y) TO TRUE
PERFORM display-ant-cell
COMPUTE ant-direction =
FUNCTION MOD(ant-direction + 1, 4)
ELSE
SET black (ant-x, ant-y) TO TRUE
PERFORM display-ant-cell
COMPUTE ant-direction =
FUNCTION MOD(ant-direction - 1, 4)
END-IF
EVALUATE TRUE
WHEN upward
ADD 1 TO ant-y
WHEN rightward
ADD 1 TO ant-x
WHEN downward
SUBTRACT 1 FROM ant-y
WHEN leftward
SUBTRACT 1 FROM ant-x
END-EVALUATE
.
display-ant-cell.
SUBTRACT ant-y FROM Grid-Size GIVING display-y
IF black (ant-x, ant-y)
DISPLAY SPACE AT LINE display-y COLUMN ant-x
WITH BACKGROUND-COLOR Black-Background
ELSE
DISPLAY SPACE AT LINE display-y COLUMN ant-x
WITH BACKGROUND-COLOR White-Background
END-IF
.
display-initial-grid.
PERFORM VARYING i FROM 1 BY 1 UNTIL i > Grid-Size
AFTER j FROM 1 BY 1 UNTIL j > Grid-Size
DISPLAY SPACE AT LINE i COLUMN j
WITH BACKGROUND-COLOR White-Background
END-PERFORM
.</syntaxhighlight>
=={{header|CoffeeScript}}==
<
class Ant
constructor: (@world) ->
Line 608 ⟶ 1,872:
console.log "Ant is at #{ant.location}, direction #{ant.direction}"
world.draw()
</syntaxhighlight>
output
<syntaxhighlight lang="text">
> coffee langstons_ant.coffee
Ant is at -24,46, direction W
Line 693 ⟶ 1,957:
_____##_________________________________________
______##________________________________________
</syntaxhighlight>
=={{header|Common Lisp}}==
<syntaxhighlight lang="lisp">(defmacro toggle (gv) `(setf ,gv (not ,gv)))
(defun langtons-ant (width height start-x start-y start-dir)
(let ( (grid (make-array (list width height)))
(x start-x)
(y start-y)
(dir start-dir) )
(loop while (and (< -1 x width) (< -1 y height)) do
(if (toggle (aref grid x y))
(setq dir (mod (1+ dir) 4))
(setq dir (mod (1- dir) 4)))
(case dir
(0 (decf y))
(1 (incf x))
(2 (incf y))
(3 (decf x)))
)
grid
)
)
(defun show-grid (grid)
(destructuring-bind (width height) (array-dimensions grid)
(dotimes (y height)
(dotimes (x width)
(princ (if (aref grid x y) "#" ".")))
(princ #\Newline))
)
)
(setf *random-state* (make-random-state t))
(show-grid (langtons-ant 100 100 (+ 45 (random 10)) (+ 45 (random 10)) (random 4)))</syntaxhighlight>
=={{header|D}}==
===Textual Version===
<syntaxhighlight lang="d">void main() @safe {
import std.stdio, std.traits;
enum width = 75, height = 52;
enum maxSteps = 12_000;
enum Direction { up, right, down, left }
enum Color : char { white = '.', black = '#' }
uint x = width / 2, y = height / 2;
Color[width][height] M;
auto dir = Direction.up;
with (Color)
for (int i = 0; i < maxSteps && x < width && y < height; i++) {
immutable turn = M[y][x] == black;
dir = [EnumMembers!Direction][(dir + (turn ? 1 : -1)) & 3];
M[y][x] = (M[y][x] == black) ? white : black;
final switch(dir) with (Direction) {
case up: y--; break;
case right: x--; break;
case down: y++; break;
case left: x++; break;
}
}
writefln("%(%-(%c%)\n%)", M);
}</syntaxhighlight>
{{out}}
<pre>...........................................................................
...........................................................................
...........................................................................
...........................................................................
.............................##..############..##
.........................
........................
........................
..................
..................
.................
................
...............
.................
...............
..............
.............
.............
..............
............
...........
..........
.........
...........#..###..#.
......
.....#..###..#.#.....#....#...####.#..#####
....###...#..##......
...#..###..#.#.....
..###...#..##......
.#..###..#.#..............
###...#..##..........
...##..#.#.......
##..#..##........
.#.#.#.#........
####.##..........
#.##.#........
.####.........
..##........
................
........
........
.........
..........
.................
...........................................................................
...........................................................................
...........................................................................</pre>
===Image Version===
This similar version requires the module from the Grayscale Image Task to generate and save a PGM image.
<syntaxhighlight lang="d">import std.stdio, std.algorithm, std.traits, grayscale_image;
void main() {
enum width = 100, height = 100;
enum nSteps = 12_000;
enum Direction { up, right, down, left }
auto M = new Image!Gray(width, height);
M.clear(Gray.white);
uint x = width / 2, y = height / 2;
auto dir = Direction.up;
for (int i = 0; i < nSteps && x < width && y < height; i++) {
immutable turn = M[x, y] == Gray.black;
dir = [EnumMembers!Direction][(dir + (turn ? 1 : -1)) & 3];
M[x, y] = (M[x, y] == Gray.black) ? Gray.white : Gray.black;
final switch(dir) with (Direction) {
case up: y--; break;
case right: x--; break;
case down: y++; break;
case left: x++; break;
}
}
M.savePGM("langton_ant.pgm");
}</syntaxhighlight>
=={{header|Dyalect}}==
<syntaxhighlight lang="dyalect">let xInc = [0, 1, -1, 0]
let yInc = [-1, 0, 0, 1]
let north = 0
let east = 1
let west = 2
let south = 3
let leftTurns = [ west, north, south, east ]
let rightTurns = [ east, south, north, west ]
func move(ant) {
ant.position.x += xInc[ant.direction]
ant.position.y += yInc[ant.direction]
}
func Array.Step(ant) {
var ptCur = (var x: ant.position.x + ant.origin.x, var y: ant.position.y + ant.origin.y)
var leftTurn = this[ptCur.x][ptCur.y]
ant.direction =
if leftTurn {
leftTurns[ant.direction]
} else {
rightTurns[ant.direction]
}
this[ptCur.x][ptCur.y] = !this[ptCur.x][ptCur.y]
move(ant)
ptCur = (x: ant.position.x + ant.origin.x, y: ant.position.y + ant.origin.y)
ant.outOfBounds =
ptCur.x < 0 ||
ptCur.x >= ant.width ||
ptCur.y < 0 ||
ptCur.y >= ant.height
ant.position
}
func newAnt(width, height) {
(
var position: (var x: 0, var y: 0),
var origin: (x: width / 2, y: height / 2),
var outOfBounds: false,
var isBlack: [],
var direction: east,
var width: width,
var height: height
)
}
func run() {
let w = 100
let h = 100
let blacks = Array.Empty(w, () => Array.Empty(h, false))
let ant = newAnt(w, h)
while !ant.outOfBounds {
blacks.Step(ant)
}
var iRow = 0;
while iRow < w {
var iCol = 0;
var ln = ""
while iCol < h {
ln += if blacks[iCol][iRow] {
"#"
} else {
" "
}
iCol += 1
}
print(ln)
iRow += 1
}
}
run()</syntaxhighlight>
{{out}}
Empty lines are omitted.
<pre> # #
## # #
# ### ##
#### ### #
##### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## # ##
### # ## ##
# ## ## ## #
#### ### # # ###
# # # ## #### #
### # # # # ## #
### # ## # ## # ##
# # ## # # ##
# # # ##### # #
# ##### ## ######
### ## # ## # # # ## # ##
## # ####### # # ### ## #
# # ###### ## # # ## # #
# # # ## # ###### ####### #
# #### ## # #### ## ## # ## #
# #### # # ###### ## ###
# # ## # ### # ## ## ###
####### # ## ## # #
#### ## ## #### ## ## ## # #
# # # ### ## ### # #### #
### ### # # ##### # # #
# # ### #### ## # ## ### ## #
## ## #### #### # # # #
# # ## ### ### ### #
## ## ### #### # ### ## #
## # #### # # # ## ### ## #
#### ## ## #### # # # # ### #
# ## ### # # ## # # # # # #
# # # ## ## # # ### ##
## # # ##### # # # # #
# ## # # ## ## # ### ###
# # # # # # ### ## ## #
### # ##### ###### ### ####### # ##
# # # ##### ## ##### #####
# ## # # # ## ### ###
#### ##### ######### # #
## # # ### # # # ### ###
# # #### ## ### ## ### ## ##
### # ## # ##### # # # ## ###
# ##### # # ## ## # # # #
###### #### ## # # ## # # ##
## # ### ## #### # ###
# # ##### # # ## # # #
## ### ####### # # ##
# # ## ## # ## #
# # #### ### ## #
# ## ### ## ##
##
##</pre>
=={{header|EasyLang}}==
[https://easylang.dev/show/#cod=bZHLDoIwEEX3/Yq7VAlNa0wMifgjhIXhEUiUmopA/94ZKILBJn3k9M70zvReNCiTFFopHHgVT2syvCrTQ0IKAKWxcIih0BpEESNPhw2lUZeU0E3JEJAmgE5JqBcJjYfpCrpzP9AWWQu9Vkqx2qWQkzv7bjgWeW1nk/mQ8CMJ+dE0Q410xM7jUPubEfdVfefnr+z/1uR0vIx++ewW7CbsTXSUaVva3I+/NSNE5wVsNsaOtwBH0nZ76kKOE4u9hgJjLoVEc143IvdF3ASu/6xwUlCCf0p8AA== Run it]
<syntaxhighlight lang="text">
len f[] 100 * 100
proc show . .
for y = 0 to 99
for x = 0 to 99
if f[y * 100 + x + 1] = 1
move x y
rect 1 1
.
.
.
.
proc run x y dir . .
dx[] = [ 0 1 0 -1 ]
dy[] = [ -1 0 1 0 ]
while x >= 0 and x < 100 and y >= 0 and y < 100
v = f[y * 100 + x + 1]
f[y * 100 + x + 1] = 1 - v
dir = (dir + 2 * v) mod 4 + 1
x += dx[dir]
y += dy[dir]
.
.
run 70 40 0
show
</syntaxhighlight>
=={{header|EchoLisp}}==
We implement multi-colored ants, as depicted in the article. An ant is described using L(eft)R(ight) patterns. LR is the basic black and white ant, other are RRLLLRRL or RRLLLRLLLRRR. See results for s [http://www.echolalie.org/echolisp/images/ant-1.png black-and-white] or [http://www.echolalie.org/echolisp/images/ant-2.png colored] ants.
<syntaxhighlight lang="scheme">
(lib 'plot)
(lib 'types)
(define (move iter x dir constant: plane turns cmax width xmax (cidx 0))
(while (> iter 0)
;; get color index of current square
(set! cidx (vector-ref plane x))
;; turn
(if (vector-ref turns cidx)
(set! dir (if (= dir 3) 0 (1+ dir))) ;; right is #t
(set! dir (if (= dir 0) 3 (1- dir))))
;; rotate colors
(set! cidx (if (= cidx cmax) 0 (1+ cidx)))
(vector-set! plane x cidx)
;; move
;; x = v + h*width for a pixel at (h,v)
(set! x
(cond
((= dir 0) (1+ x))
((= dir 1) (+ x width))
((= dir 2) (1- x))
((= dir 3) (- x width))))
(when (or (< x 0) (>= x xmax)) (set! iter -666)) ;; out of bounds
(set! iter (1- iter)))
iter)
;; a color table of 16 colors
(define colors
(list 0 (rgb 1 1 1) (rgb 1 0 0) (rgb 0 1 0) (rgb 0 0 1) (rgb 1 1 0) (rgb 1 0 1) (rgb 0 1 1)))
(define colors (list->vector (append colors colors)))
;; transform color index into rgb color, using colors table.
(define (colorize plane xmax)
(for ((x xmax))
(vector-set! plane x (vector-ref colors (vector-ref plane x))))
(vector->pixels plane)
xmax )
;; ant's patterns
(define turns #(#t #t #f #f #f #t #f #f #f #t #t #t)) ;; RRLLLRLLLRRR
;;(define turns #(#t #t #f #f #f #t #t #f)) ; RRLLLRRL
;;(define turns #(#t #f)) ; RL : basic ant
(define (ant (iter 100000))
(plot-clear)
(define width (first (pixels-dim))) ;; plane dimensions
(define height (rest (pixels-dim)))
(define plane (pixels->uint32-vector))
(define x (+ (quotient width 2) (* width (quotient height 2)))) ;; middle of plane
(define xmax (* width height))
(move iter x 0 plane turns (1- (vector-length turns)) width xmax)
(colorize plane xmax))
(ant) ;; run
</syntaxhighlight>
=={{header|Ela}}==
A straightforward implementation (assumes that we start with ant looking forward):
<syntaxhighlight lang="ela">open list core generic
type Field = Field a
type Color = White | Black
type Direction = Lft | Fwd | Rgt | Bwd
field s = Field [[White \\ _ <- [1..s]] \\ _ <- [1..s]]
isBlack Black = true
isBlack _ = false
newfield xc yc (Field xs) = Field (newfield' 0 xs)
where newfield' _ [] = []
newfield' n (x::xs)
| n == yc = row 0 x :: xs
| else = x :: newfield' (n+1) xs
where row _ [] = []
row n (x::xs)
| n == xc = toggle x :: xs
| else = x :: row (n+1) xs
where toggle White = Black
toggle Black = White
showPath (Field xs) = toString <| show' "" xs
where show' sb [] = sb +> ""
show' sb (x::xs) = show' (showRow sb x +> "\r\n") xs
where showRow sb [] = sb +> ""
showRow sb (x::xs) = showRow (sb +> s) xs
where s | isBlack x = "#"
| else = "_"
move s xc yc = move' (Fwd,xc,yc) (field s)
where move' (pos,xc,yc)@coor fld
| xc >= s || yc >= s || xc < 0 || yc < 0 = fld
| else = fld |> newfield xc yc |> move' (matrix (dir fld) coor)
where dir (Field xs)
| `isBlack` (xs:yc):xc = Lft
| else = Rgt
matrix Lft (pos,x,y) = go (left pos,x,y)
matrix Rgt (pos,x,y) = go (right pos,x,y)
go (Lft,x,y) = (Lft,x - 1,y)
go (Rgt,x,y) = (Rgt,x+1,y)
go (Fwd,x,y) = (Fwd,x,y - 1)
go (Bwd,x,y) = (Bwd,x,y+1)
right Lft = Fwd
right Fwd = Rgt
right Rgt = Bwd
right Bwd = Lft
left Lft = Bwd
left Bwd = Rgt
left Rgt = Fwd
left Fwd = Lft</syntaxhighlight>
This implementation is pure (doesn't produce side effects).
Testing:
<syntaxhighlight lang="ela">showPath <| move 100 50 50</syntaxhighlight>
Output (empty lines are skipped to save space):
<pre>__________________________________________##__############__##______________________________________
_________________________________________#__####__________#__##_____________________________________
________________________________________###___##____________##_#____________________________________
________________________________________#_#__#_________#__#____#____________________________________
____________________________________##__##_#_#_________###_______#__________________________________
_________________________________###_#__#___#_____#_____##_##__###__________________________________
__________________________________#_#__###__##_####_##___#_#__#_##__##______________________________
__________________________________#_###_##__#_##__###_#_#_____###___###_____________________________
________________________________#_____#___#####_#_#__####__#___###_#_#_#____________________________
_______________________________###_##___#_####__##_##_######_#_###_#___#____________________________
_______________________________#_###_#_##_#_#_##_##_##_#___#####_###_##_____________________________
___________________________________#_#___#_##_###___#___#_#__####____#_##___________________________
________________________________#__#_________##_##___#__##_____##_#_____##__________________________
_______________________________###___#_#_##_###__#__##_____#___###_##__##_#_________________________
______________________________#__###__##___##_##___###__#____#__##_####___#_________________________
_____________________________###___#___#_#__#_#_####_##__#_##_###__#_____#__________________________
____________________________#__###__#_##____#__#_###__#______###_##_#__#__##________________________
___________________________###___#_____#_##_#_##__##__#####_####__####_##___#_______________________
__________________________#__###__#_#_#__#_###_#_#_##______##___#_#_#____#___#______________________
_________________________###___#__##_###__##_#___##_______####_####___#______#______________________
________________________#__###__#_#__#___##__###########_#__####__#____#____#_______________________
_______________________###___#__##______#_####__##__#########__#__##____#__##_______________________
______________________#__###__#_#___##__#_##___##_##_###_###___#__#_##__####_#______________________
_____________________###___#__##___#__#_######_##_#_##_#_#____###_###___##___#______________________
____________________#__###__#_#___#_____#####_#_#####_____#_#__##_#____##___#_______________________
___________________###___#__##____#_____#_##_#####_##__#_#___#__#__##_#__#__#_______________________
__________________#__###__#_#_____#____#___####_#__#####_##___##########___##_______________________
_________________###___#__##______#_##___##___#__#___####__#___##_####_##___________________________
________________#__###__#_#________#####_#__##___##_#___#____#_#__#__#__#_#_________________________
_______________###___#__##__________##__##_#_#_#____##_##_#_#_##__#__##__##_________________________
______________#__###__#_#_________________#__#____#_########_#_#_##__####_#_________________________
_____________###___#__##__________________#__#___#_______##_##___#__#__##_#_________________________
____________#__###__#_#____________________#__#__#______#__##__##___##_####_________________________
___________###___#__##______________________##___#_______##__##____#___#_###________________________
__________#__###__#_#____________________________#_##__####____####_###_####________________________
_________###___#__##______________________________##__####____##__#_##_#_#__#_______________________
________#__###__#_#________________________________##____##____##_###_##_#####______________________
_______###___#__##________________________________________________#_##_#__####______________________
______#__###__#_#_____________________________________________________##_##_##______________________
_____###___#__##______________________________________________________##____________________________
____#__###__#_#_____________________________________________________#_##__####_#____________________
___###___#__##_____________________________________________________#__#_###__###____________________
__#__###__#_#______________________________________________________#_##_#__#__#_____________________
_###___#__##________________________________________________________##______##______________________
#__###__#_#__________________________________________________________##_____________________________
_###_#__##__________________________________________________________________________________________
#_#_#_#_#___________________________________________________________________________________________
_####_##____________________________________________________________________________________________
_#_##_#_____________________________________________________________________________________________
__####______________________________________________________________________________________________
___##_______________________________________________________________________________________________
</pre>
=={{header|Elixir}}==
{{works with|Elixir|1.1+}}
{{trans|Ruby}}
<syntaxhighlight lang="elixir">defmodule Langtons do
def ant(sizex, sizey) do
{px, py} = {div(sizex,2), div(sizey,2)} # start position
move(MapSet.new, sizex, sizey, px, py, {1,0}, 0)
end
defp move(plane, sx, sy, px, py, _, step) when px<0 or sx<px or py<0 or sy<py, do:
print(plane, sx, sy, px, py, step)
defp move(plane, sx, sy, px, py, dir, step) do
{plane2, {dx,dy}} = if {px,py} in plane,
do: {MapSet.delete(plane, {px,py}), turn_right(dir)},
else: {MapSet.put(plane, {px,py}), turn_left(dir)}
move(plane2, sx, sy, px+dx, py+dy, {dx,dy}, step+1)
end
defp turn_right({dx, dy}), do: {dy, -dx}
defp turn_left({dx, dy}), do: {-dy, dx}
defp print(plane, sx, sy, px, py, step) do
IO.puts "out of bounds after #{step} moves: (#{px}, #{py})"
Enum.each(0..sy, fn j ->
IO.puts Enum.map(0..sx, fn i -> if {i,j} in plane, do: "#", else: "." end)
end)
end
end
Langtons.ant(100, 100)</syntaxhighlight>
{{out}}
<pre style="height:40ex;overflow:scroll">
out of bounds after 11669 moves: (26, -1)
..........................#.#........................................................................
........................##.#.#.......................................................................
.......................#.###.##......................................................................
......................####.###.#.....................................................................
......................#####.#..##....................................................................
.......................#...##.##.#...................................................................
........................###...#..##..................................................................
.........................#...##.##.#.................................................................
..........................###...#..##................................................................
...........................#...##.##.#...............................................................
............................###...#..##..............................................................
.............................#...##.##.#.............................................................
..............................###...#..##............................................................
...............................#...##.##.#...........................................................
................................###...#..##..........................................................
.................................#...##.##.#.........................................................
..................................###...#..##........................................................
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=={{header|Elm}}==
<syntaxhighlight lang="elm">import Maybe as M
import Matrix
import Time exposing (Time, every, second)
import List exposing (..)
import String exposing (join)
import Html exposing (div, h1, text)
import Html.App exposing (program)
import Svg
import Svg.Attributes exposing (version, viewBox, cx, cy, r, x, y, x1, y1, x2, y2, fill,style, width, height, preserveAspectRatio)
w = 700
h = 700
dt = 0.0001
type Direction = North | West | South | East
type alias Model =
{ rows : Int
, cols : Int
, boxes : Matrix.Matrix Bool
, location : Matrix.Location
, direction : Direction
}
initModel : Int -> Int -> Model
initModel cols rows =
{ rows = rows
, cols = cols
, boxes = Matrix.matrix rows cols (\location -> False)
, location = (rows//2,cols//2)
, direction = North
}
view model =
let
borderLineStyle = style "stroke:black;stroke-width:0.3"
x1Min = x1 <| toString 0
y1Min = y1 <| toString 0
x1Max = x1 <| toString model.cols
y1Max = y1 <| toString model.rows
x2Min = x2 <| toString 0
y2Min = y2 <| toString 0
x2Max = x2 <| toString model.cols
y2Max = y2 <| toString model.rows
borders = [ Svg.line [ x1Min, y1Min, x2Max, y2Min, borderLineStyle ] []
, Svg.line [ x1Max, y1Min, x2Max, y2Max, borderLineStyle ] []
, Svg.line [ x1Max, y1Max, x2Min, y2Max, borderLineStyle ] []
, Svg.line [ x1Min, y1Max, x2Min, y2Min, borderLineStyle ] []
]
circleInBox (row,col) color =
Svg.circle [ r "0.25"
, fill (color)
, cx (toString (toFloat col + 0.5))
, cy (toString (toFloat row + 0.5))
] []
showUnvisited location box =
if box then [circleInBox location "black" ]
else []
unvisited = model.boxes
|> Matrix.mapWithLocation showUnvisited
|> Matrix.flatten
|> concat
maze = [ Svg.g [] <| borders ++ unvisited ]
in
div
[]
[ h1 [] [text "Langton's Ant"]
, Svg.svg
[ version "1.1"
, width (toString w)
, height (toString h)
, viewBox (join " "
[ 0 |> toString
, 0 |> toString
, model.cols |> toString
, model.rows |> toString ])
]
maze
]
updateModel : Model -> Model
updateModel model =
let current = model.location
inBox = snd current >= 0 && snd current < model.cols
&& fst current >= 0 && fst current < model.rows
in if not inBox then
model
else
let currentValue = Matrix.get current model.boxes |> M.withDefault False
dir = case (model.direction, currentValue) of
(North, True) -> East
(East, True) -> South
(South, True) -> West
(West, True) -> North
(North, False) -> West
(East, False) -> North
(South, False) -> East
(West, False) -> South
next = case dir of
North -> (fst current+1, snd current)
South -> (fst current-1, snd current)
East -> (fst current, snd current+1)
West -> (fst current, snd current-1)
boxes = Matrix.set current (not currentValue) model.boxes
in {model | boxes=boxes, location=next, direction=dir}
type Msg = Tick Time
subscriptions model = every (dt * second) Tick
main =
let
update msg model = (updateModel model, Cmd.none)
init = (initModel 100 100 , Cmd.none)
in program
{ init = init
, view = view
, update = update
, subscriptions = subscriptions
}</syntaxhighlight>
Link to live demo: https://dc25.github.io/langtonsAntElm/
=={{header|Erlang}}==
Over-engineered sine I have summer vacation. Ex: Display function only display lines with black cells.
<syntaxhighlight lang="erlang">
-module( langtons_ant ).
-export( [task/0] ).
-record( neighbour, {north, south, east, west} ).
-record( state, {colour=white, controller, max_x, max_y, neighbour, position} ).
task() ->
Controller = erlang:self(),
Max_x = Max_y = 100,
Pid_positions = plane_create( Controller, Max_x, Max_y ),
Pids = [X || {X, _} <- Pid_positions],
[X ! {pid_positions, Pid_positions} || X <- Pids],
{Pid, _Position} = lists:keyfind( {Max_x div 2, Max_y div 2}, 2, Pid_positions ),
Pid ! {ant_start, north, Controller},
receive
{ant_arrives, _Pid} -> ok
end,
display( Controller, Max_x, Max_y, Pids ),
[X ! {stop, Controller} || X <- Pids].
display( Controller, Max_x, Max_y, Pids ) ->
Positions_colours = display_positions_colours( Pids, Controller ),
All_lines = [display_line( Max_x, Positions_colours, Y ) || Y <- lists:seq(Max_y, 1, -1)],
Lines_with_black = [X || X <- All_lines, lists:member(black, X)],
[io:fwrite( "~s~n", [[display_on_screen(X) || X <- Lines]] ) || Lines <- Lines_with_black].
display_line( Max_x, Positions_colours, Y ) -> [proplists:get_value({X,Y}, Positions_colours, white) || X <- lists:seq(1, Max_x)].
display_on_screen( white ) -> $_;
display_on_screen( black ) -> $#.
display_positions_colours( Pids, Controller ) ->
[X ! {position_colour, Controller} || X <- Pids],
[display_positions_colours_receive() || _X <- Pids].
display_positions_colours_receive( ) ->
receive
{position_colour, Position, Colour} -> {Position, Colour}
end.
loop( State ) ->
receive
{pid_positions, Pid_positions} ->
{_My_position, Neighbour} = lists:foldl( fun loop_neighbour/2, {State#state.position, #neighbour{}}, Pid_positions ),
erlang:garbage_collect(), % Shrink process after using large Pid_positions. For memory starved systems.
loop( State#state{neighbour=Neighbour} );
{ant_start, Direction, Controller} when Controller =:= State#state.controller ->
{Pid, New_state} = loop_ant_departs( Direction, State ),
Pid ! {ant_arrives, erlang:self()},
loop( New_state );
{ant_arrives, From} ->
{Direction, New_state} = loop_ant_arrives( From, State ),
{To, Newest_state} = loop_ant_departs( Direction, New_state ),
To ! {ant_arrives, erlang:self()},
loop( Newest_state );
{position_colour, Controller} when Controller =:= State#state.controller ->
Controller ! {position_colour, State#state.position, State#state.colour},
loop( State );
{stop, Controller} when Controller =:= State#state.controller -> ok
end.
loop_ant_arrives( Pid, State ) ->
Neighbour = State#state.neighbour,
From = loop_ant_arrives_direction( Pid, Neighbour ),
{loop_ant_arrives_new_direction(From, State), State}.
loop_ant_arrives_direction( Pid, #neighbour{north=Pid} ) -> north;
loop_ant_arrives_direction( Pid, #neighbour{south=Pid} ) -> south;
loop_ant_arrives_direction( Pid, #neighbour{east=Pid} ) -> east;
loop_ant_arrives_direction( Pid, #neighbour{west=Pid} ) -> west.
loop_ant_arrives_new_direction( north, #state{colour=white} ) -> west;
loop_ant_arrives_new_direction( north, #state{colour=black} ) -> east;
loop_ant_arrives_new_direction( south, #state{colour=white} ) -> east;
loop_ant_arrives_new_direction( south, #state{colour=black} ) -> west;
loop_ant_arrives_new_direction( east, #state{colour=white} ) -> north;
loop_ant_arrives_new_direction( east, #state{colour=black} ) -> south;
loop_ant_arrives_new_direction( west, #state{colour=white} ) -> south;
loop_ant_arrives_new_direction( west, #state{colour=black} ) -> north.
loop_ant_departs( north, #state{position={_X,Y}, max_y=Y}=State ) ->
{State#state.controller, State};
loop_ant_departs( south, #state{position={_X,1}}=State ) ->
{State#state.controller, State};
loop_ant_departs( east, #state{position={X,_Y}, max_x=X}=State ) ->
{State#state.controller, State};
loop_ant_departs( west, #state{position={1,_Y}}=State ) ->
{State#state.controller, State};
loop_ant_departs( Direction, State ) ->
Neighbour = State#state.neighbour,
Pid = loop_ant_departs_pid( Direction, Neighbour ),
{Pid, State#state{colour=other_colour(State)}}.
loop_ant_departs_pid( north, #neighbour{north=Pid} ) -> Pid;
loop_ant_departs_pid( south, #neighbour{south=Pid} ) -> Pid;
loop_ant_departs_pid( east, #neighbour{east=Pid} ) -> Pid;
loop_ant_departs_pid( west, #neighbour{west=Pid} ) -> Pid.
loop_neighbour( {Pid, {X, Y}}, {{X, My_y}, Neighbour} ) when Y =:= My_y + 1 -> {{X, My_y}, Neighbour#neighbour{north=Pid}};
loop_neighbour( {Pid, {X, Y}}, {{X, My_y}, Neighbour} ) when Y =:= My_y - 1 -> {{X, My_y}, Neighbour#neighbour{south=Pid}};
loop_neighbour( {Pid, {X, Y}}, {{My_x, Y}, Neighbour} ) when X =:= My_x + 1 -> {{My_x, Y}, Neighbour#neighbour{east=Pid}};
loop_neighbour( {Pid, {X, Y}}, {{My_x, Y}, Neighbour} ) when X =:= My_x - 1 -> {{My_x, Y}, Neighbour#neighbour{west=Pid}};
loop_neighbour( _Pid_position, Acc ) -> Acc.
other_colour( #state{colour=white} ) -> black;
other_colour( #state{colour=black} ) -> white.
plane_create( Controller, Max_x, Max_y ) -> [{plane_create_cell(Controller, Max_x, Max_y, {X, Y}), {X,Y}} || X <- lists:seq(1, Max_x), Y<- lists:seq(1, Max_y)].
plane_create_cell( Controller, Max_x, Max_y, Position ) -> erlang:spawn_link( fun() -> loop( #state{controller=Controller, max_x=Max_x, max_y=Max_y, position=Position} ) end ).
</syntaxhighlight>
{{out}}
<pre style="height:30ex;overflow:scroll">
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</pre>
=={{header|Euphoria}}==
{{works with|Euphoria|4.0.3, 4.0.0 RC1 and later}}
<syntaxhighlight lang="euphoria">include std\console.e
include std\graphics.e
sequence grid = repeat(repeat(1,100),100) --fill 100 by 100 grid with white (1)
sequence antData = {48, 53, 360} --ant x coordinate, y coordinate, facing angle
integer iterations = 0
--while ant isn't out of bounds of the 100 by 100 area..
while antData[1] > 0 and antData[1] < 100 and antData[2] > 0 and antData[2] < 100 do
switch grid[antData[1]][antData[2]] do
case 1 then--cell is already white
grid[antData[1]][antData[2]] = 0 --cell turns black, ant turns right
antData[3] += 90
break
case 0 then--cell is already black
grid[antData[1]][antData[2]] = 1 --cell turns white, ant turns left
antData[3] -= 90
break
end switch
--wrap ant directions if > 360 or < 90 (by 90)
switch antData[3] do
case 450 then
antData[3] = 90
break
case 0 then
antData[3] = 360
break
end switch
--move ant based on its new facing, one square
--first north, then south, east, west
switch antData[3] do
case 360 then
antData[2] -= 1
break
case 180 then
antData[2] += 1
break
case 90 then
antData[1] += 1
break
case 270 then
antData[1] -= 1
break
end switch
iterations += 1
end while
wrap(0) --don't wrap text output, the grid wouldnt display as a square
for y=1 to 100 do
printf(1,"\n")
for x=1 to 100 do
switch grid[x][y] do--each grid block , based on color
case 0 then
printf(1,".")
break
case 1 then
printf(1,"#")
break
end switch
end for
end for
printf(1,"\n%d Iterations\n",iterations)
any_key()--wait for keypress, put default message 'press any key..'</syntaxhighlight>[[File:LangtonsAnt_Euphoria_SDL.png|right|thumb|SDL output]]
Code needed to run SDL example with Mark Akita's SDL_gfx_Test1.exw (as template) included with his SDL_gfx package from rapideuphoria.com's archive -
In initialization section :<syntaxhighlight lang="euphoria">
sequence grid = repeat(repeat(1,100),100) --fill 100 by 100 grid with white (1)
sequence antData = {48, 53, 360} --x coordinate, y coordinate, facing angle</syntaxhighlight>
In main() , after keystate=SDL_GetKeyState(NULL) , you can adapt the program above to draw the ant's step each frame.
Use dummy=pixelColor(surface,x+20,y+12,#000000FF) (for example) to replace the text output.
Just before the close of the while loop, use dummy=pixelColor(surface,antData[1]+20,antData[2]+12,#FF0000FF) for the ant
and SDL_UpdateRect(surface,0,0,0,0) to display the graphic.
=={{header|F Sharp|F#}}==
<syntaxhighlight lang="fsharp">
// Langton's ant F# https://rosettacode.org/wiki/Langton%27s_ant
// A list of cells which are black is maintained and then printed out at the end
type Cell = { X : int; Y : int }
type Direction = | North | South | East| West // direction the ant is facing
let withinBounds (dim:int) (cell: Cell) = // ant's cell within dimensions ?
cell.X < dim && cell.Y < dim && cell.X >= 0 && cell.Y >= 0
let rotateLeft (currentDirection: Direction) =
match currentDirection with
| North -> West | South -> East | East -> North | West -> South
let rotateRight (currentDirection: Direction ) =
match currentDirection with
| North -> East | South -> West | East -> South | West -> North
let nextCell (dir:Direction) (cell: Cell) = // compute next cell based on the direction
match dir with
| North -> {cell with Y = cell.Y + 1 }
| South -> {cell with Y = cell.Y - 1 }
| East -> {cell with X = cell.X + 1 }
| West -> {cell with X = cell.X - 1 }
let isBlackCell (blackCells: Cell list) (cell:Cell) =
blackCells |> List.exists ( fun c -> c = cell)
let toggleCellColor (blackCells: Cell list) (cell: Cell) =
if cell |> isBlackCell blackCells
then blackCells |> List.where( fun c -> c <> cell) // remove the cell from list of black cells
else cell::blackCells // add the cell to the list of black cells
let moveToCell (blackCells: Cell list) (currentDir : Direction) (cell: Cell) =
let ndir = if cell |> isBlackCell blackCells // next step direction is computed
then rotateLeft currentDir
else rotateRight currentDir
let nlst = cell |> toggleCellColor blackCells // next step updated list of black cells is computed
let ncell = cell |> nextCell ndir // next step cell is computedd
(nlst, ndir, ncell) // return next step list of black cells, direction it will enter the cell, new cell
let rec doStep (dim:int) (blackCells: Cell list) (dir : Direction) (cell: Cell) =
let (nlst, ndir, ncell) = moveToCell blackCells dir cell
if withinBounds dim ncell // check if the next step is within bounds
then doStep dim nlst ndir ncell // recursive call to next step
else nlst, ndir, ncell
[<EntryPoint>]
let main _ =
let dim = 100
let (blacklist, _, _) = doStep dim [] North { X = dim/2 ; Y = dim/2 } // start with empty blacklist, facing north in the center
// print out by row, 0th row is at the bottom
seq { for row in [dim-1..-1..0] do for col in [0..dim-1] -> (col,row) }
|> Seq.iter (fun (row,col) -> if {X = row; Y = col } |> isBlackCell blacklist
then printf "#" else printf " "
if row = (dim - 1 )
then printf "\n" else ()
)
0
</syntaxhighlight>
<pre>
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# ### # # # ##### # ##### # # ## # ## #
### # ## # # ## ##### ## # # # # ## # # #
# ### # # # # #### # ##### ## ########## ##
### # ## # ## ## # # #### # ## #### ##
# ### # # ##### # ## ## # # # # # # # #
### # ## ## ## # # # ## ## # # ## # ## ##
# ### # # # # # ######## # # ## #### #
### # ## # # # ## ## # # ## #
# ### # # # # # # ## ## ## ####
### # ## ## # ## ## # # ###
# ### # # # ## #### #### ### ####
### # ## ## #### ## # ## # # #
# ### # # ## ## ## ### ## #####
### # ## # ## # ####
# ### # # ## ## ##
### # ## ##
# ### # # # ## #### #
### # ## # # ### ###
# ### # # # ## # # #
### # ## ## ##
# ### # # ##
### # ##
# # # # #
#### ##
# ## #
####
##
</pre>
=={{header|Fantom}}==
<
class World
{
Line 911 ⟶ 3,285:
}
}
</syntaxhighlight>
Output (snipping the blank lines):
Line 968 ⟶ 3,342:
Finished in 11669 iterations
</pre>
=={{header|Forth}}==
{{works with|GNU Forth|0.7.0}}
All array manipulations were taken from Rosetta Code examples.
<syntaxhighlight lang="forth">
1 0 0 0 \ pushes orientation of the ant to the stack.
100 CONSTANT border \ lenght of the side of the grid
border border * constant size \ size of the grid
variable antpos \ for storing position of the ant
size 2 / border 2 / + antpos ! \ positions ant in the middle of the grid
create Grid size cells allot
here constant GridEnd \ creates an array to hold the grid
: turn.left
>r rot r> SWAP ; \ rotates ant anti-clockwise
: turn.right
turn.left turn.left turn.left ; \ rotates ant clockwise
: stop.ant
antpos @ DUP 0< SWAP size > + ; \ checks if ant not out of bounds
: call.pos
Grid antpos @ cells + @ ; \ pushes ant position to the stack
: grid.add
Grid antpos @ cells + @ -1 + Grid antpos @ cells + ! ; \ pushes -1 to the current position of the ant on the grid
: swap.pos
call.pos dup * Grid antpos @ cells + ! ; \ multiplies current grid cell by itself to turn -1 into 1
: swap.col
grid.add swap.pos ; \ changes current grid cell color
: go.ant \ moves ant one step in the direction taken from the stack
2over 2over \ copies stack for testing
1 = IF antpos @ border + antpos ! 2DROP DROP ELSE \ if true moves ant one cell up, drops unused numbers from stack
1 = IF antpos @ 1 + antpos ! 2DROP ELSE \ same, but moves to the right
1 = IF antpos @ border - antpos ! DROP ELSE \ here to the left
1 = IF antpos @ 1 - antpos ! ELSE \ and down
THEN THEN THEN THEN ;
: step.ant \ preforms one full step.
call.pos 1 = IF turn.left swap.col ELSE
turn.right swap.col
THEN go.ant ;
: run.ant \ runs the ant until it leaves the grid
BEGIN
step.ant
stop.ant UNTIL ;
: square.draw \ draws an "*" if grid cell is one or " " if zero
1 = IF 42 EMIT ELSE 32 EMIT THEN ;
: draw.grid \ draws grid on screen
PAGE \ clear sreen
size 0 DO I
I border MOD 0= IF CR THEN \ breaks the grid into lines
Grid I cells + @ square.draw DROP
LOOP ;
: langton.ant run.ant draw.grid ; \ launches the ant, outputs the result
</syntaxhighlight>
{{out}}
<pre style="height:60ex;overflow:scroll">
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</pre>
=={{header|Fortran}}==
{{works with|Fortran|90 and later}}
<syntaxhighlight lang="fortran">program Langtons_Ant
implicit none
integer, parameter :: csize = 100
integer :: direction = 0, maxsteps = 20000
integer :: i, x, y
logical :: cells(csize,csize) = .true.
logical :: cflag
x = csize / 2; y = x
do i = 1, maxsteps
cflag = cells(x,y)
if(cflag) then
direction = direction + 1
if(direction == 4) direction = direction - 4
else
direction = direction - 1
if(direction == -1) direction = direction + 4
end if
cells(x,y) = .not. cells(x,y)
select case(direction)
case(0)
y = y - 1
case(1)
x = x + 1
case(2)
y = y + 1
case(3)
x = x - 1
end select
if(x < 1 .or. x > csize .or. y < 1 .or. y > csize) exit
end do
do y = 1, csize
do x = 1, csize
if(cells(x,y)) then
write(*, "(a)", advance="no") "."
else
write(*, "(a)", advance="no") "#"
end if
end do
write(*,*)
end do
end program</syntaxhighlight>
{{out}} (Cropped to save space)
<pre style="height:60ex;overflow:scroll">
...................................................................................
...................................................................................
.........................................##..############..##......................
........................................#..####..........#..##.....................
.......................................###...##............##.#....................
.......................................#.#..#.........#..#....#....................
...................................##..##.#.#.........###.......#..................
................................###.#..#...#.....#.....##.##..###..................
.................................#.#..###..##.####.##...#.#..#.##..##..............
.................................#.###.##..#.##..###.#.#.....###...###.............
...............................#.....#...#####.#.#..####..#...###.#.#.#............
..............................###.##...#.####..##.##.######.#.###.#...#............
..............................#.###.#.##.#.#.##.##.##.#...#####.###.##.............
..................................#.#...#.##.###...#...#.#..####....#.##...........
...............................#..#.........##.##...#..##.....##.#.....##..........
..............................###...#.#.##.###..#..##.....#...###.##..##.#.........
.............................#..###..##...##.##...###..#....#..##.####...#.........
............................###...#...#.#..#.#.####.##..#.##.###..#.....#..........
...........................#..###..#.##....#..#.###..#......###.##.#..#..##........
..........................###...#.....#.##.#.##..##..#####.####..####.##...#.......
.........................#..###..#.#.#..#.###.#.#.##......##...#.#.#....#...#......
........................###...#..##.###..##.#...##.......####.####...#......#......
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.......#..###..#.#................................##....##....##.###.##.#####......
......###...#..##................................................#.##.#..####......
.....#..###..#.#.....................................................##.##.##......
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...#..###..#.#.....................................................#.##..####.#....
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...................................................................................
...................................................................................</pre>
===But, if one remembers complex numbers===
<syntaxhighlight lang="fortran">
PROGRAM LANGTONSANT
C Langton's ant wanders across an initially all-white board, stepping one cell at a go.
C If the current cell is white, it becomes black and the ant turns right.
C If the current cell is black, it becomes white and the ant turns left.
C The ant advances one cell in its latest direction, and reconsiders.
INTEGER ENUFF
PARAMETER (ENUFF = 100) !Said to be so.
CHARACTER*1 CELL(ENUFF,ENUFF) !The work area.
COMPLEX WAY,PLACE !A direction and a position.
INTEGER X,Y,XN,Y1 !Integer versions.
INTEGER STEP !A counter.
CELL = "" !Clear for action.
PLACE = CMPLX(ENUFF/2,ENUFF/2) !Start at the middle.
WAY = (1,0) !Initial direction is +x.
Commence wandering.
DO STEP = 1,20000 !Enough to be going on with.
X = REAL(PLACE) !Change languages.
Y = AIMAG(PLACE) !Could mess about with EQUIVALENCE...
IF (X.LE.0 .OR. X.GT.ENUFF !Are we still
1 .OR.Y.LE.0 .OR. Y.GT.ENUFF) THEN!Within bounds?
WRITE (6,1) STEP - 1,X,Y !No! Offer details.
1 FORMAT ("Step ",I0," to (",I0,",",I0,") is out of bounds!")
EXIT !And wander no further.
END IF !But, if we're within bounds,
IF (CELL(X,Y).NE."#") THEN !Consider our position.
CELL(X,Y) = "#" !A blank cell becomes black. Ish.
WAY = WAY*(0,-1) !Turn right.
ELSE !Otherwise,
CELL(X,Y) = "+" !A black cell becomes white. Ish.
WAY = WAY*(0,+1) !Turn left.
END IF !So much for changing direction.
PLACE = PLACE + WAY !Advance one step.
END DO !On to the next step.
Consider the bounds...
DO Y1 = 1,ENUFF !Work up from the bottom.
IF (ANY(CELL(:,Y1).NE." ")) EXIT !The last line with a splot.
END DO !Subsequent lines would be blank.
DO XN = ENUFF,1,-1 !Work back from the right hand side.
IF (ANY(CELL(XN,:).NE." ")) EXIT !The last column with a splot.
END DO !Subsequent columns would be blank.
Cast forth the splotches.
DO Y = ENUFF,Y1,-1 !The topmost y-coordinate first!
WRITE (6,"(666A1)") CELL(1:XN,Y) !Roll a line's worth.
END DO !On to the next line.
Completed.
END
</syntaxhighlight>
Output is the same, except for orientation. Here I have stuck to (x,y) Cartesian orientation rather than lines (y) increasing downwards. Just for fun, + signs mark cells that have been trampled and then cleaned. But not to pure white... Notice that some interior cells have never been trampled.
{{out}}
<pre style="height:60ex;overflow:scroll">
Step 11669 to (26,101) is out of bounds!
#+#
## #+#
#+###+##
####+###+#
#####+#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+#
###+++#++##
#+++##+##+# ##
###+++#++## +##
#+++##+##++##+++#
#### ###+++#+++#++###
#++++# #+++##+####+++#
###++++# #+#++++++#+##+#
###++++# ## +++#+##++#+##
#++++# +## #+#+++++##++
#+#++++++#+#####++#+++#+
#+++#####++++++++++##+######
###++##++#+##+#+#+#+++##+#+##
## +#+#######+#+++#++###++++##+#
#++#++######+##+++#++#+## ++#+++#
#++++#+#+##+#++######+#######+++#
#+####+##+#+####++++##++##+#+##+#
#++++####+++#++#+######+##++++###
#+++#+##+#+###+#++##++##+++###
+++#######++++#++##+##+#+++++#
#### +##+##++####+##+##+##++#+++++#
#++++#+#+++###+##+###++++#+####++++#
###+++++++###+#+#+#####++++#+#++++++#
#+#+++###+####+##+#+++##+###+##+++++#
++++##+##++####++++####+#+#+#+++++#
#++++#++##+++###++###+++++###++++++#
##+++##+###+####++#++++++###+++##++#
##+#+####+++++#+++#++#+##+###+##+++#
####+##+++##+####++#+#++#++#++###+++#
#+##+###++#+#+##+#+#+++++#+#+++++#+#
++#+#++#++++##+##++#+#++###+##+++
++##+#++++#++#####+#++++#++++#++#+#
+#+##+#++#++++##+##+#++###++++++###
#+#+++#++#++#++#++###+++##++##++++#
###+#+#####+######+###+#######+#+##
#+#+#++++#####+++##++#####+#####+
#++##+++#++++++#++#+##++###+###
####+++#####+#########+++#+#+++
## +#++#+++++###+#+#+++#+###++###+
#++# ####+##+++###+##+++###+##+++++##
###++++#+##+#+#####+++#++++#++#++##+###
#+#####+#+#+++##++##++++ #++++#+ #++#
++######+####++## #+++#+ ##++#+# ##
##++++++#+###+##++####++ #+++###
#++#+#####++#+++#+##+++#+ #++#
##+###+#######+++++#+++++# ##
#+#++##+##++++++#+++##++++#
#++#+#### ###++##++#
#+##+### ## ##
##+
##
</pre>
=={{header|FreeBASIC}}==
<syntaxhighlight lang="freebasic">' version 16-10-2016
' compile with: fbc -s gui
' a cell size of 4 x 4 pixels is used
' In FreeBASIC the 0,0 is the top left corner
ScreenRes 400,400,8 ' give a 100 by 100 field
Dim As UByte Ptr p = ScreenPtr
If p = 0 Then End ' p does not point to screen
Palette 0, 0, 0, 0 ' index 0 = black
Palette 255, 255, 255, 255 ' index 225 = white
Line (0, 0) - (799, 799), 255, bf ' draw box and fill it with white color
Dim As Integer count, offset, x = 199, y = 199
Dim As UByte col ' = color
' direction, 0 = up, 1 = right, 2 = down, 3 = left
Dim As UByte d ' d = 0, looking up
Do
offset = x + y * 400
col = p[offset]
If col = 0 Then
d = (d -1) And 3
Else
d = (d +1) And 3
EndIf
col = col Xor 255 ' flip the color
ScreenLock ' don't update screen while we are drawing
' draw a 4*4 block and paint it with palette color [0 | 255]
Line (x, y) - (x +3, y -3), col, bf
ScreenUnLock ' allow screen update's
'Sleep 100 ' slow the program down if needed
' true = 0, false = -1
If (d And 1) = 1 Then
x = x + (d = 1) * 4 - (d = 3) * 4
Else
y = y - (d = 0) * 4 + (d = 2) * 4
End If
count += 1
' update step count window title bar
WindowTitle "Langton's ant step: " + Str(count)
' has user clicked on close window "X" then end program
If InKey = Chr(255) + "k" Then End
Loop Until x < 1 Or x > 398 Or y < 1 Or y > 398
' display total count in window title bar
WindowTitle "Langton's ant has left the field in " + Str(count) + " steps"
' empty keyboard buffer
While InKey <> "" : Wend
'Print : Print "hit any key to end program"
Sleep
End</syntaxhighlight>
=={{header|Furor}}==
<syntaxhighlight lang="furor">
###sysinclude X.uh
$ff0000 sto szin1
$ffffff sto szin2
2 sto pausetime
maxypixel 100 - sto YRES
maxxpixel sto XRES
zero ant
// Az ant iránykódjai:
// 0 : fel
// 1 : le
// 2 : jobbra
// 3 : balra
@XRES 2 / sto antx // Az ant kezdeti koordinátái
@YRES 2 / sto anty
myscreen "Furor monitor" @YRES @XRES graphic // Create the graphic screen
."Kilépés: ESC\n"
infiniteloop: {... // infinite loop begins
myscreen @anty @antx [[]][[]] // A pixel színe amin az ant ül épp
@szin2 == { myscreen @anty @antx @szin1 [][] // másik színre átállítjuk a pixelt
2 // Jobbra fog fordulni
}{ myscreen @anty @antx @szin2 [][] // másik színre átállítjuk a pixelt
3 // Balra fog fordulni
}
// Elvégezzük az új koordináta beállítását:
sto direction
@ant 0 == { @direction 2 == then §r1 @direction 3 == then §r2 }
@ant 2 == { @direction 2 == then §r3 @direction 3 == then §r4 }
@ant 1 == { @direction 3 == { r1: antx @XRES ring 2 goto §beolvas } @direction 2 == { r2: antx @XRES !ring 3 goto §beolvas } }
@ant 3 == { @direction 3 == { r3: anty @YRES !ring 1 goto §beolvas } @direction 2 == { r4: anty @YRES ring 0 goto §beolvas } }
beolvas: sto ant
myscreen key? sto! billkód @pausetime usleep $1b ==
|...}
."Made " {...}§infiniteloop print ." steps.\n"
."XRES = " @XRES printnl
."YRES = " @YRES printnl
myscreen !graphic
end
{ „myscreen” }
{ „billkód” }
{ „pausetime” }
{ „XRES” }
{ „YRES” }
{ „szin1” }
{ „szin2” }
{ „ant” }
{ „antx” }
{ „anty” }
{ „direction” }
</syntaxhighlight>
=={{header|Peri}}==
<syntaxhighlight lang="peri">
###sysinclude standard.uh
###sysinclude system.uh
###sysinclude str.uh
###sysinclude X.uh
#g
$ff0000 sto szin1
$ffffff sto szin2
10 sto pausetime
//maxypixel 100 - sto YRES
//maxypixel 20 - sto YRES
//maxypixel 7 - sto YRES
//maxypixel 13 - sto YRES
maxypixel 20 - sto YRES
maxxpixel sto XRES
zero ant
// Az ant iránykódjai:
// 0 : fel
// 1 : le
// 2 : jobbra
// 3 : balra
@XRES 2 / sto antx // Az ant kezdeti koordinátái
@YRES 2 / sto anty
myscreen "Furor monitor" @YRES @XRES graphic // Create the graphic screen
."Kilépés: ESC\n"
{.. // infinite loop begins
myscreen @anty @antx getpixel // A pixel színe amin az ant ül épp
@szin2 == {
myscreen @anty @antx @szin1 setpixel // másik színre átállítjuk a pixelt
2 // Jobbra fog fordulni
}{
myscreen @anty @antx @szin2 setpixel // másik színre átállítjuk a pixelt
3 // Balra fog fordulni
}
// Elvégezzük az új koordináta beállítását:
sto direction
@ant 0 == @direction 2 == & { ++() antx @antx @XRES == { zero antx } 2 sto ant goto §beolvas }
@ant 0 == @direction 3 == & { @antx inv { @XRES -- sto antx }{ --() antx } 3 sto ant goto §beolvas }
@ant 1 == @direction 3 == & { ++() antx @antx @XRES == { zero antx } 2 sto ant goto §beolvas }
@ant 1 == @direction 2 == & { @antx inv { @XRES -- sto antx }{ --() antx } 3 sto ant goto §beolvas }
@ant 2 == @direction 2 == & { @anty inv { @YRES -- sto anty }{ --() anty } 1 sto ant goto §beolvas }
@ant 2 == @direction 3 == & { ++() anty @anty @YRES == { zero anty } 0 sto ant goto §beolvas }
@ant 3 == @direction 2 == & { ++() anty @anty @YRES == { zero anty } 0 sto ant goto §beolvas }
@ant 3 == @direction 3 == & { @anty inv { @YRES -- sto anty }{ --() anty } 1 sto ant goto §beolvas }
beolvas:
myscreen key !sto billkód @pausetime inv sleep $1b == {
."Made " {..} print ." generations.\n" {.>.} }
..}
myscreen inv graphic
end
{ „myscreen” }
{ „billkód” }
{ „pausetime” }
{ „XRES” }
{ „YRES” }
{ „szin1” }
{ „szin2” }
{ „ant” }
{ „antx” }
{ „anty” }
{ „direction” }
</syntaxhighlight>
=={{header|Gambas}}==
<syntaxhighlight lang="gambas">'This code will create a GUI Form to display the result
hGridView As GridView 'The display is on a GridView
iCol As Integer = 38 'Column start position
iRow As Integer = 30 'Row start position
Public Sub Form_show()
SetUpForm 'Run the SetUpForm routine
Go 'Run the Go routine
End
Public Sub Go() 'This is what does the work
Dim siDir As Short = 3 'Stores the Direction of the ant 0 = North, 1 = East, 2 = South ,3 = West
Dim siCount As Short 'Counter
Repeat 'Repeat loop
Inc siCount 'Increase siCount
If hGridView[iRow, iCol].background = -1 Then 'If the Background of the cell is white then..(Right turn)
hGridView[iRow, iCol].background = 0 'Make the Background black
siDir = Direction(siDir, True) 'Get the direction to turn
If siDir = 0 Then Dec iRow 'Decrease Row if facing North
If siDir = 1 Then Inc iCol 'Increase Column if facing East
If siDir = 2 Then Inc iRow 'Increase Row if facing South
If siDir = 3 Then Dec iCol 'Decrease Column if facing West
End If
'Wait 'This will allow you to see the Grid being populated. Rem it out for an instant result
If hGridView[iRow, iCol].background = 0 Then 'If the Background of the cell is black then.. Left Turn
hGridView[iRow, iCol].background = -1 'Make the Background white
siDir = Direction(siDir, False) 'Get the direction to turn
If siDir = 0 Then Dec iRow 'Decrease Row if facing North
If siDir = 1 Then Inc iCol 'Increase Column if facing East
If siDir = 2 Then Inc iRow 'Increase Row if facing South
If siDir = 3 Then Dec iCol 'Decrease Column if facing West
End If
Until siCount = 9660 'Loop 9660 times
End
Public Sub Direction(siDirection As Short, bWay As Boolean) As Byte 'To workout which way to go
If bWay Then 'If turning Right then
Inc siDirection 'Increase siDirection e.g. 0 = North to 1 = East
Else 'Else if turning Left
Dec siDirection 'Decrease siDirection e.g. 2 = South to 1 = East
End If
If siDirection < 0 Then siDirection = 3 'To address 0 - 1 = -1
If siDirection > 3 Then siDirection = 0 'To address 3 + 1 = 4
Return siDirection 'Return the correct direction
End
Public Sub SetUpForm() 'Set up the Form and Create the Gridview
With Me 'Change the Properties of the Form
.Height = 1012 'Set the Form Height
.Width = 1012 'Set the Form Width
.Arrangement = Arrange.Vertical 'Set the Form Arrangement
.Padding = 5 'Set the Form Padding (Border)
.title = "Langton's ant" 'Set the Form Title
End With
hGridView = New GridView(Me) 'Create a GridView
With hGridView 'Change the Properties of the GridView
.Columns.count = 100 'Create 100 Columns
.Rows.count = 100 'Create 100 Rows
.Columns.Width = 10 'Set the Column Width
.Rows.Height = 10 'Set the Column Height
.expand = True 'Set the Gridview to Expand to fill the Form
.background = -1 'Set the Gridview background to White
End With
End</syntaxhighlight>
'''[http://www.cogier.com/gambas/Langton's%20ant.png Click here for an image of the result]'''
=={{header|GFA Basic}}==
To make it easier to see the output on small Atari screens, the output is written to a text file.
<syntaxhighlight lang="basic">
'
' Langton's ant
'
' World is a global boolean array, 100x100 in size
width%=100
height%=100
DIM world!(width%,height%)
ARRAYFILL world!(),FALSE
' Time in world
time%=0
' Ant is represented by a global three-element array
' holding: x, y, direction [0=north,1=west,2=south,3=east]
DIM ant%(3)
'
@setup_ant
@run_ant
@display_world
'
' Displays the world to file "langton.out": . for false, # for true
'
PROCEDURE display_world
LOCAL i%,j%
OPEN "o",#1,"langton.out"
PRINT #1,"Time in world: ";time%;" ticks"
FOR i%=0 TO width%-1
FOR j%=0 TO height%-1
IF world!(i%,j%)
PRINT #1,"#";
ELSE
PRINT #1,".";
ENDIF
NEXT j%
PRINT #1,""
NEXT i%
CLOSE #1
RETURN
'
' Set up the ant to start at (50,50) facing north
'
PROCEDURE setup_ant
ant%(0)=50
ant%(1)=50
ant%(2)=0
RETURN
'
' check if ant position is within world's bounds
'
FUNCTION ant_in_world
RETURN ant%(0)>=0 AND ant%(0)<width% AND ant%(1)>=0 AND ant%(1)<height%
ENDFUNC
'
' Turn ant direction to left
'
PROCEDURE ant_turn_left
ant%(2)=(ant%(2)+1) MOD 4
RETURN
'
' Turn ant direction to right
'
PROCEDURE ant_turn_right
ant%(2)=(ant%(2)+3) MOD 4
RETURN
'
' Ant takes a step forward in current direction
'
PROCEDURE ant_step_forward
SELECT ant%(2)
CASE 0
ant%(0)=ant%(0)+1
CASE 1
ant%(1)=ant%(1)+1
CASE 2
ant%(0)=ant%(0)-1
CASE 3
ant%(1)=ant%(1)-1
ENDSELECT
RETURN
'
' Run the ant until it falls out of the world
'
PROCEDURE run_ant
WHILE @ant_in_world
time%=time%+1
IF world!(ant%(0),ant%(1)) ! true for white
world!(ant%(0),ant%(1))=FALSE
@ant_turn_left
ELSE ! false for black
world!(ant%(0),ant%(1))=TRUE
@ant_turn_right
ENDIF
@ant_step_forward
WEND
RETURN
</syntaxhighlight>
=={{header|Go}}==
[[file:GoAnt.png|right|thumb|Output png]]
<
import (
Line 1,023 ⟶ 4,163:
fmt.Println(err)
}
}</
=={{header|Haskell}}==
The set of black cells is represented as a set of points. Complementary set is regarded as white cells.
Necessary import:
<syntaxhighlight lang="haskell">import Data.Set (member,insert,delete,Set)</syntaxhighlight>
In order to express the ant's algorithm literally we define two operators:
<syntaxhighlight lang="haskell">-- functional sequence
(>>>) = flip (.)
-- functional choice
p ?>> (f, g) = \x -> if p x then f x else g x</syntaxhighlight>
Finally define the datatype representing the state of ant and ant's universe
<syntaxhighlight lang="haskell">data State = State { antPosition :: Point
, antDirection :: Point
, getCells :: Set Point }
type Point = (Float, Float)</syntaxhighlight>
Now we are ready to express the main part of the algorithm
<syntaxhighlight lang="haskell">step :: State -> State
step = isBlack ?>> (setWhite >>> turnRight,
setBlack >>> turnLeft) >>> move
where
isBlack (State p _ m) = member p m
setBlack (State p d m) = State p d (insert p m)
setWhite (State p d m) = State p d (delete p m)
turnRight (State p (x,y) m) = State p (y,-x) m
turnLeft (State p (x,y) m) = State p (-y,x) m
move (State (x,y) (dx,dy) m) = State (x+dx, y+dy) (dx, dy) m</syntaxhighlight>
That's it.
Here is the solution of the task:
<syntaxhighlight lang="haskell">task :: State -> State
task = iterate step
>>> dropWhile ((< 50) . distance . antPosition)
>>> getCells . head
where distance (x,y) = max (abs x) (abs y)</syntaxhighlight>
For given initial configuration it returns the set of black cells at the end of iterations.
We can display it graphically using Gloss library
<syntaxhighlight lang="haskell">import Graphics.Gloss
main = display w white (draw (task initial))
where
w = InWindow "Langton's Ant" (400,400) (0,0)
initial = State (0,0) (1,0) mempty
draw = foldMap drawCell
drawCell (x,y) = Translate (10*x) (10*y) $ rectangleSolid 10 10</syntaxhighlight>
Or animate the ant's trajectory
<syntaxhighlight lang="haskell">main = simulate w white 500 initial draw (\_ _ -> step)
where
w = InWindow "Langton's Ant" (400,400) (0,0)
initial = State (0,0) (1,0) mempty
draw (State p _ s) = pictures [foldMap drawCell s, color red $ drawCell p]
drawCell (x,y) = Translate (10*x) (10*y) $ rectangleSolid 10 10</syntaxhighlight>
=={{header|Icon}} and {{header|Unicon}}==
[[file:LangtonsAnt_unicon_100x100_11655.gif|right|thumb]]
<
procedure main(A)
Line 1,078 ⟶ 4,281:
WAttrib(label)
WDone()
end</
{{libheader|Icon Programming Library}}
Line 1,086 ⟶ 4,289:
=={{header|J}}==
<
langton=:3 :0
loc=. <.-:$cells=. (_2{.y,y)$dir=. 0
Line 1,096 ⟶ 4,299:
end.
' #' {~ cells
)</
<pre style="font-size: 2px"> langton 100 100
Line 1,199 ⟶ 4,402:
</pre>
=={{header|Java}}==
This implementation allows for sizes other than 100x100, marks the starting position with a green box (sometimes hard to see at smaller zoom levels and the box is smaller than the "pixels" so it doesn't cover up the color of the "pixel" it's in), and includes a "zoom factor" (<code>ZOOM</code>) in case the individual "pixels" are hard to see on your monitor.
<
import java.awt.Graphics;
Line 1,224 ⟶ 4,428:
g.setColor(Color.GREEN);
g.fillRect(plane[0].length / 2 * ZOOM,
}
};
Line 1,243 ⟶ 4,447:
int xChange = 0, yChange = -1; //start moving up
while(antX < width && antY < height && antX >= 0 && antY >= 0){
if(plane[antY][antX]){
//turn left
Line 1,263 ⟶ 4,466:
}
}
plane[antY][antX] = !plane[antY][antX];
antX += xChange;
antY += yChange;
Line 1,268 ⟶ 4,472:
return plane;
}
}</
Output (click for a larger view):
[[Image:Langton Java.png|250px]]
=={{header|JavaScript}}==
Utilises the HTML5 canvas element to procedurally generate the image... I wanted to see the progress of the grid state as it was generated, so this implementation produces a incrementally changing image until an 'ant' hits a cell outside of the coordinate system. It can also accept multiple ants, this adds minimal complexity with only the addition of an 'ants' array which is iterated in each step, no additional conditions are necessary to simulate multiple ants, they coexist quite well... good ants ! 1st argument is an array of ant objects, 2nd argument is an object property list of options to change grid size, pixel size and interval (animation speed).
<syntaxhighlight lang="javascript">
// create global canvas
var canvas = document.createElement('canvas');
canvas.id = 'globalCanvas';
document.body.appendChild(canvas);
function langtonant(antx, optx) {
'use strict';
var x, y, i;
// extend default opts
var opts = {
gridsize: 100,
pixlsize: 4,
interval: 4
};
for (i in optx) {
opts[i] = optx[i];
}
// extend default ants
var ants = [{
x: 50,
y: 50,
d: 0
}];
for (i in antx) {
ants[i] = antx[i];
}
// initialise grid
var grid = [];
for (x = 0; x < opts.gridsize; x ++) {
grid[x] = [];
for (y = 0; y < opts.gridsize; y ++) {
grid[x][y] = true;
}
}
// initialise directions
var dirs = [
{x: 1, y: 0},
{x: 0, y: -1},
{x: -1, y: 0},
{x: 0, y: 1}
];
// initialise canvas
var canv = document.getElementById('globalCanvas');
var cont = canv.getContext('2d');
canv.width = opts.gridsize * opts.pixlsize;
canv.height = opts.gridsize * opts.pixlsize;
// initialise pixels
var pixlblac = cont.createImageData(opts.pixlsize, opts.pixlsize);
for (i = 0; i < (opts.pixlsize * opts.pixlsize * 4); i += 4) {
pixlblac.data[i + 3] = 255;
}
var pixlwhit = cont.createImageData(opts.pixlsize, opts.pixlsize);
for (i = 0; i < (opts.pixlsize * opts.pixlsize * 4); i += 4) {
pixlwhit.data[i + 3] = 0;
}
// run simulation
function simulate() {
var sane = true;
// iterate over ants
for (i = 0; i < ants.length; i ++) {
var n = ants[i];
// invert, draw, turn
if (grid[n.x][n.y]) {
grid[n.x][n.y] = false;
cont.putImageData(pixlblac, n.x * opts.pixlsize, n.y * opts.pixlsize);
n.d --;
} else {
grid[n.x][n.y] = true;
cont.putImageData(pixlwhit, n.x * opts.pixlsize, n.y * opts.pixlsize);
n.d ++;
}
// modulus wraparound
n.d += dirs.length;
n.d %= dirs.length;
// position + direction
n.x += dirs[n.d].x;
n.y += dirs[n.d].y;
// sanity check
sane = (n.x < 0 || n.x > opts.gridsize || n.y < 0 || n.y > opts.gridsize) ? false : sane;
}
// loop with interval
if (sane) {
setTimeout(simulate, opts.interval);
}
}
simulate();
}
</syntaxhighlight>
Usage: default ants, custom opts
<syntaxhighlight lang="javascript">
langtonant({}, {
gridsize: 100,
pixlsize: 4,
interval: 4
});
</syntaxhighlight>
{{out}}
[http://jsbin.com/ocuwal/1/edit Live Version]
[[Image:Langtons Ant - JavaScript 1.png]]
Usage: custom ants, default opts
<syntaxhighlight lang="javascript">
langtonant([
{
x: (100 / 2) + 7,
y: (100 / 2) + 7,
d: 1
}, {
x: (100 / 2) + 7,
y: (100 / 2) - 7,
d: 2
}, {
x: (100 / 2) - 7,
y: (100 / 2) - 7,
d: 3
}, {
x: (100 / 2) - 7,
y: (100 / 2) + 7,
d: 0
}
]);
</syntaxhighlight>
{{out}}
[http://jsbin.com/ahumuz/1/edit Live Version]
[[Image:Langtons Ant - JavaScript 2.png]]
'''More functional approach to Javascript.'''
Requires lodash. Wants a canvas with id = "c"
<syntaxhighlight lang="javascript">
///////////////////
// LODASH IMPORT //
///////////////////
// import all lodash functions to the main namespace, but isNaN not to cause conflicts
_.each(_.keys(_), k => window[k === 'isNaN' ? '_isNaN' : k] = _[k]);
const
WORLD_WIDTH = 100,
WORLD_HEIGHT = 100,
PIXEL_SIZE = 4,
DIRTY_COLOR = '#000',
VIRGIN_COLOR = '#fff',
RUNS = 10000,
SPEED = 50,
// up right down left
DIRECTIONS = [0, 1, 2, 3],
displayWorld = (world) => each(world, (row, rowidx) => {
each(row, (cell, cellidx) => {
canvas.fillStyle = cell === 1 ? DIRTY_COLOR : VIRGIN_COLOR;
canvas.fillRect(rowidx * PIXEL_SIZE, cellidx * PIXEL_SIZE, PIXEL_SIZE, PIXEL_SIZE);
});
}),
moveAnt = (world, ant) => {
world[ant.x][ant.y] = world[ant.x][ant.y] === 1 ? 0 : 1;
ant.dir = DIRECTIONS[(4 + ant.dir + (world[ant.x][ant.y] === 0 ? 1 : -1)) % 4];
switch (ant.dir) {
case DIRECTIONS[0]:
ant.y -= 1;
break;
case DIRECTIONS[1]:
ant.x -= 1;
break;
case DIRECTIONS[2]:
ant.y += 1;
break;
case DIRECTIONS[3]:
ant.x += 1;
break;
}
return [world, ant];
},
updateWorld = (world, ant, runs) => {
[world, ant] = moveAnt(world, ant);
displayWorld(world);
if (runs > 0) setTimeout(partial(updateWorld, world, ant, --runs), SPEED);
},
canvas = document.getElementById('c').getContext('2d');
let
world = map(range(WORLD_HEIGHT), i => map(range(WORLD_WIDTH), partial(identity, 0))),
ant = {
x: WORLD_WIDTH / 2,
y: WORLD_HEIGHT / 2,
dir: DIRECTIONS[0]
};
canvas.canvas.width = WORLD_WIDTH * PIXEL_SIZE;
canvas.canvas.height = WORLD_HEIGHT * PIXEL_SIZE;
updateWorld(world, ant, RUNS);
</syntaxhighlight>
=={{header|jq}}==
In the following, the grid is boolean, and white is represented by true.
<syntaxhighlight lang="jq">
def matrix(m; n; init):
if m == 0 then [range(0;n)] | map(init)
elif m > 0 then [range(0;m)][ range(0;m) ] = matrix(0;n;init)
else error("matrix\(m);_;_) invalid")
end;
def printout:
. as $grid
| ($grid|length) as $height
| ($grid[0]|length) as $width
| reduce range(0;$height) as $i ("\u001B[H"; # ANSI code
. + reduce range(0;$width) as $j ("\n";
. + if $grid[$i][$j] then " " else "#" end ) );
def langtons_ant(grid_size):
def flip(ant):
# Flip the color of the current square
.[ant[0]][ant[1]] = (.[ant[0]][ant[1]] | not)
;
# input/output: the ant's state: [x, y, direction]
# where direction is one of (0,1,2,3)
def move(grid):
# If the cell is black, it changes to white and the ant turns left;
# If the cell is white, it changes to black and the ant turns right;
(if grid[.[0]][.[1]] then 1 else 3 end) as $turn
| .[2] = ((.[2] + $turn) % 4)
| if .[2] == 0 then .[0] += 1
elif .[2] == 1 then .[1] += 1
elif .[2] == 2 then .[0] += -1
else .[1] += -1
end
;
# state: [ant, grid]
def iterate:
.[0] as $ant | .[1] as $grid
# exit if the ant is outside the grid
| if $ant[0] < 1 or $ant[0] > grid_size
or $ant[1] < 1 or $ant[1] > grid_size
then [ $ant, $grid ]
else
($grid | flip($ant)) as $grid
| ($ant | move($grid)) as $ant
| [$ant, $grid] | iterate
end
;
((grid_size/2) | floor | [ ., ., 0]) as $ant
| matrix(grid_size; grid_size; true) as $grid
| [$ant, $grid] | iterate
| .[1]
| printout
;
langtons_ant(100)</syntaxhighlight>
{{Out}}
The output is the same as for [[#Rexx|Rexx]] below.
=={{header|Julia}}==
{{works with|Julia|1.0}}
<syntaxhighlight lang="julia">
function ant(width, height)
y, x = fld(height, 2), fld(width, 2)
M = falses(height, width)
dir = im
for i in 0:100000
x in 1:width && y in 1:height || break
dir *= M[y, x] ? im : -im
M[y, x] = !M[y, x]
x, y = reim(x + im * y + dir)
end
for row in 1:size(M,1)
println(mapreduce(x -> x ? 'x' : '.', *, M[row,:]))
end
end
ant(100, 100)
</syntaxhighlight>
=={{header|Kotlin}}==
{{trans|D}}
<syntaxhighlight lang="scala">// version 1.2.0
enum class Direction { UP, RIGHT, DOWN, LEFT }
const val WHITE = 0
const val BLACK = 1
fun main(args: Array<String>) {
val width = 75
val height = 52
val maxSteps = 12_000
var x = width / 2
var y = height / 2
val m = Array(height) { IntArray(width) }
var dir = Direction.UP
var i = 0
while (i < maxSteps && x in 0 until width && y in 0 until height) {
val turn = m[y][x] == BLACK
val index = (dir.ordinal + if (turn) 1 else -1) and 3
dir = Direction.values()[index]
m[y][x] = if (m[y][x] == BLACK) WHITE else BLACK
when (dir) {
Direction.UP -> y--
Direction.RIGHT -> x--
Direction.DOWN -> y++
Direction.LEFT -> x++
}
i++
}
for (j in 0 until height) {
for (k in 0 until width) print(if(m[j][k] == WHITE) '.' else '#')
println()
}
}</syntaxhighlight>
{{out}}
<pre>
Same as D entry (textual version)
</pre>
"Go to the ant, O sluggard; consider her ways, and be wise. Without having any chief, officer, or ruler, she prepares her bread in summer and gathers her food in harvest." For Dr. Kaser.
=={{header|LC-3}}==
"Go to the ant, O sluggard; consider her ways, and be wise. Without having any chief, officer, or ruler, she prepares her bread in summer and gathers her food in harvest." For Dr. Kaser.
<syntaxhighlight lang="lc-3">
.orig x3000
ld r1, ASCIIDIFF1
; user input for grid size
lea r0, STGRIDSIZE
puts
in
add r0, r0, r1
add r0, r0, #-1
brz SELECTED100
ld r0, GRID300
st r0, GRIDSIZE
brnzp GRIDSELECTED
SELECTED100
ld r0, GRID100
st r0, GRIDSIZE
GRIDSELECTED
; User input for number of additional ants
lea r0, STHOWMANY
puts
in
add r1, r1, r0 ; r1 = number of additional ants
add r1, r1, #1
st r1, LIVINGANTS
; INITIALIZE FIRST ANT
and r7, r7, x0
add r7, r7, #9 ; loop counter for the other ants
and r1, r1, x0 ; x and y coordinates go in here
and r3, r3, x0 ; to be mapped to a cell id
; check grid size for starting coordinates
ld r4, GRIDSIZE
ld r6, GRID100
not r6, r6
add r6, r6, #1
add r6, r6, r4 ; grid size - 100
brz GRID100B
ld r1, START300
ld r3, START300
brnzp FIRSTANTCOORDINATES
GRID100B
ld r1, START100
ld r3, START100
FIRSTANTCOORDINATES
JSR MAPPY ; takes r1 and r3 values, converts to cell id in r5
ld r6, LIVEANTTEMPLATE ; = x8000, alive and facing north
add r6, r6, r5 ; complete antword for ant 1
lea r4, ANTWORD
str r6, r4, #0 ; put first ant in base address of ANTWORD array
ld r2, LIVINGANTS
ANTSETUPLOOP
add r4, r4, #1 ; increment address of ant
add r2, r2, #-1
brnz INITIALIZEDEAD
JSR ANTCOORDS
JSR MAPPY
ld r6, LIVEANTTEMPLATE
add r6, r5, r6
brnzp READYTOSTORE
INITIALIZEDEAD
and r6, r6, x0
READYTOSTORE
str r6, r4, #0
add r7, r7, #-1
brnz DONESETUP
brnzp ANTSETUPLOOP
DONESETUP
BIGMOVELOOP ; one iteration of this loop moves all 10 ants (doing nothing if they're dead)
ld r1, LIVINGANTS
brz EVERYONEISDEAD
ld r1, ANTWORD
; FOR LOOP TO MOVE ALL 10 ANTS
ld r1, STEPCOUNT
add r1, r1, #1
st r1, STEPCOUNT
BRNZP BIGMOVELOOP
EVERYONEISDEAD ; :(
halt
STGRIDSIZE .stringz "Grid size? 1 for 100, 3 for 300 "
STHOWMANY .stringz "How many additional ants? "
ASCIIDIFF1 .fill #-48
SUBTEMP1 .fill #0
LIVINGANTS .fill #0
GRIDSIZE .fill #0
GRID100 .fill #100
GRID300 .fill #300
STEPCOUNT .fill #0
ANTWORD .blkw #10
START100 .fill #50
START300 .fill #150
LIVEANTTEMPLATE .fill x8000
ANTCOORDTEMP .fill #0
ANTCOORDTEMP2 .fill #0
;************************************************************************
;************************************************************************
; SUBROUTINES
;************************************************************************
;************************************************************************
; SUBROUTINE
ANTSONTHEMOVE
; [1] check if dead
; [2] extract current location
; [3] extract current direction
; [4] check current colour
; [5] turn
; [7] change location or kill
; INPUT: R1:
address of ant
; R4:
grid size
; LOCAL: R2: ant word
; R3: cell id of ant
st r2, MOVETEMP2
st r3, MOVETEMP3
st r5, MOVETEMP5
st r6, MOVETEMP6
st r7, MOVETEMP7
ldr r2, r1, #0 ; r2 = copy of ant-word
; [1] CHECK FOR DEATH. word for dead ants == x0000
add r2, r2, #0
brz ENDOFMOVE ; if ant-word + 0 == 0, ant is dead.
; [2] extract current location
ld r3, IDMASK ; for getting rid of first 3 bits of ant-word, leaving only location
and r3, r2, r3 ; r3 = cell id of ant
; [4] check current colour and flip it
jsr FLIPPITY ; flips bit, puts original colour in R5
; white/0: turn right; black/1: turn left
; [5] turn the ant according to pre-flipped colour
add r0, r5, #0
brnp LEFTTURN
jsr TAKEARIGHTTURN
brnzp DONETURNING
LEFTTURN
jsr TAKEALEFTTURN
DONETURNING
; [7] change location and kill
ldr r2, r1, #0 ; reload modified antword from memory
ld r5, SOUTH ; butmasks
ld r6, EAST
and r5, r5, r2
and r6, r6, r2 ; isolating the two direction bits, 2b and 3b, to determine direction
add r5, r5, #0 ; check if 2b is 0
brnp SECTIOND ;
add r6, r6, #0 ; check if 3b is 0
brnp SECTIONC
; if both are zero, direction is north
;; if cell id <= grid size, ant is already at the top and will die
not r0, r4
add r0, r0, #1 ; r0 = negative grid size
add r3, r0, r3 ; r3 = cell id - grid
brn ANTDEATHISPERMANENT ; if negative, kill it
add r2, r2, r0 ; antword - grid size
brnzp ENDOFMOVE
SECTIONC
; if direction is 01, ant faces east
;; if (cellID % grid != grid -1)
;; then cellid++, else die
not r0, r4
add r0, r0, #1
add r5, r3, #0 ; copy celll id to r5 to repeatedly subtract grid size
EASTMODLOOP
add r5, r5, r0 ; cell id - grid
add r5, r5, #1 ; if this is 0, then r5 == grid - 1
brz ANTDEATHISPERMANENT
add r5, r5, #-1 ; but if not, undo it and re-loop
brn MOVEEAST ; if negative, allowed to move east
; if equal to grid-1, ant is on eastern border and will die
BRNZP EASTMODLOOP
MOVEEAST
add r2, r2, #1 ; move east: CellID++
brnzp ENDOFMOVE
SECTIOND ; first direction bit is 1
add r6, r6, #0 ; check if second bit is 0
brnp SECTIONF
; if it is 0, then direction is 10 = south
; if ant is on southern border, it dies
; if cellID >= grid^2-grid, then ant is on southern border
ld r0, N100
add r0, r0, r3 ; checking if grid size = 100
brz GRIDIS100
ld r0, GRIDSQ300HALF
add r3, r3, r0
add r3, r3, r0
add r3, r3, r0
add r3, r3, r0
brzp ANTDEATHISPERMANENT
add r2, r2, r4
brnzp ENDOFMOVE
GRIDIS100
ld r0, GRIDSQ100
add r3, r3, r0
brzp ANTDEATHISPERMANENT
add r2, r2, r4
brnzp ENDOFMOVE
SECTIONF
; direction bits are 11 = WEST
; if cellID % grid != 0, ant can go west, otherwise dead
add r6, r3, #0 ; copy cell id to r6
not r0, r4
add r0, r0, #1 ; r0 = -grid
WESTMODLOOP
add r6, r6, r0
brz ANTDEATHISPERMANENT
brn CANMOVEWEST
brp WESTMODLOOP
CANMOVEWEST
add r2, r2, #-1
brnzp ENDOFMOVE
ANTDEATHISPERMANENT
and r2, r2, #0
ld r7, LIVINGANTS
add r7, r7, #-1
st r7, LIVINGANTS
ENDOFMOVE
str r1, r2, #0 ; double check this syntax
ld r2, MOVETEMP2
ld r3, MOVETEMP3
ld r5, MOVETEMP5
ld r6, MOVETEMP6
ld r7, MOVETEMP7
RET
N100 .fill #-100
GRIDSQ100 .fill #-9900
GRIDSQ300HALF .fill #-22425
MOVETEMP3 .fill #0
MOVETEMP2 .fill #0
MOVETEMP4 .fill #0
MOVETEMP5 .fill #0
MOVETEMP6 .fill #0
MOVETEMP7 .fill x0
IDMASK .fill x1FFF ; for extracting bits 12-0, the cell ID of the ant
; end of ANTSONTHEMOVE subroutine
FAKEXOR ; subroutine
; XOR of two registers
; INPUT r2, r4
; OUTPUT r6 = r2 XOR r4
; A in r4, not A in r5
; B in r2; not B in r6
; r4 XOR r2
st r5, XORTEMP5
not r6, r2
and r6, r6, r4 ; r6 = a & ~b
not r6, r6 ; r6 = ~(a & ~b)
not r5, r4 ; r5 = ~ a
and r5, r5, r2 ; r5 = ~a & b
not r5, r5 ; r5 = ~(~a & b)
and r6, r5, r6 ; r6 = ~(a & ~b) & ~(~a & b)
not r6, r6 ; r6 = ~( ~(a & ~b) & ~(~a & b) ) = a XOR b
ld r5, XORTEMP5
RET
XORTEMP5 .fill #0
; SUBROUTINE
FLIPPITY
; Takes a cell id and flips the bit in the grid, returns the original colour
; INPUT r1: cell id
; LOCAL r2: which bit to flip, then bitmask
; r3: quotient, then address of byte to change
; OUTOUT r5: original colour of cell id, before flipping. 1 if black, 0 if white.
;
; First, get byte (GRID + OFFSET)
; CELL ID / 16
st r4, FLIPTEMP4
st r5, FLIPTEMP5
st r6, FLIPTEMP6
and r3, r3, #0
add r2, r1, #0 ; copy cell id into r2
; loop to divide cellid by 16
FLIPLOOP
add r2, r2, #-16 ; cell id - 16
brn FLIPLOOPDONE ; if negative, division done
add r3, r3, #1 ; if not negative, increment quotient and subtract again
BRNZP FLIPLOOP
FLIPLOOPDONE
add r2, r2, #8 ; add 16 back to negative number to get cellid % 16
add r2, r2, #8 ; this is which bit within the byte that the cell ID refers to
lea r4, GRID ; starting address of GRID array
add r3, r3, r4 ; r3 = address of byte that will be changed = GRID base address + CELL ID / 16
lea r4, BM1 ; r4 = address of butmask array
add r4, r4, r2 ; r4 + which bit to flip = address of appropriate bitmask
ldr r2, r4, #0 ; r2 = bitmask to flip one bit
ldr r4, r3, #0 ; r4 = byte to be changed
and r0, r2, r4 ; indicates original colour of bit. 0 if white, non-zero if black
; A in r4, not A in r5
; B in r2; not B in r6
; r4 XOR r2
not r6, r2
and r6, r6, r4 ; r6 = a & ~b
not r6, r6 ; r6 = ~(a & ~b)
not r5, r4 ; r5 = ~ a
and r5, r5, r2 ; r5 = ~a & b
not r5, r5 ; r5 = ~(~a & b)
and r6, r5, r6 ; r6 = ~(a & ~b) & ~(~a & b)
not r6, r6 ; r6 = ~( ~(a & ~b) & ~(~a & b) ) = a XOR b
str r6, r3, #0
ld r4, FLIPTEMP4
ld r6, FLIPTEMP6
add r5, r0, #0 ; move colour of bit into r5 for output
ret
GRID .fill x8000
FLIPTEMP4 .fill #0
FLIPTEMP5 .fill #0
FLIPTEMP6 .fill #0
; bitmasks for flipping one bit
BM1 .fill x8000
BM2 .fill x4000
BM3 .fill x2000
BM4 .fill x1000
BM5 .fill x0800
BM6 .fill x0400
BM7 .fill x0200
BM8 .fill x0100
BM9 .fill x0080
BM10 .fill x0040
BM11 .fill x0020
BM12 .fill x0010
BM13 .fill x0008
BM14 .fill x0004
BM15 .fill x0002
BM16 .fill x0001
; END OF FLIPPITY SUBROUTINE
; SUBROUTINE
TAKEALEFTTURN
; turns the ant 90 degrees left
; INPUT R1: address in memory of ANT
; LOCAL R2: ant
; R3: bitmask
; R4: 3rdbit
; R5: 2nd and 3rd bit
; R6:
; R7:
; R0:
st r2, LEFTTURNTEMP2
st r3, LEFTTURNTEMP3
st r4, LEFTTURNTEMP4
st r6, LEFTTURNTEMP6
st r7, LEFTTURNTEMP7 ; store r7, load before RET
ldr r2, r1, #0 ; load ant into r2
ld r3, EAST
and r4, r2, r3 ; r4 = 3rdbit
ld r3, WEST
;and r5, r2, r3 ; r5 = 2nd and 3rd bits
add r4, r4, #0 ; check if 3rd bit is 0
brnp THIRDBIT1 ; If so, continue. If not, jump to next part.
; 3rd bit is 0, so XOR r2 ant-word with WEST bitmask, already in R3
BRNZP LEFTTURNEND
THIRDBIT1
; third bit is 1, so use EAST bitmask
ld r3, EAST
LEFTTURNEND
add r0, r4, #0 ; move r4 3rdbit into r0 temporarily
add r4, r3, #0 ; move r3 bitmask into r4 for the XOR subroutine
JSR FAKEXOR ; r6 = r2 XOR r4
; flips the correct bit to turn left
add r3, r4, #0 ; moves r4 bitmask back into r3
add r4, r0, #0 ; moves r0 3rdbit back into r3
str r6, r1, #0 ; store tweaked ant-word with new direction back in memory
ld r2, LEFTTURNTEMP2
ld r3, LEFTTURNTEMP3
ld r4, LEFTTURNTEMP4
ld r6, LEFTTURNTEMP6
ld r7, LEFTTURNTEMP7
RET
WEST .fill X6000
EAST .fill x2000
NORTH .fill x0000
SOUTH .fill x4000
LEFTTURNTEMP2 .fill #0
LEFTTURNTEMP3 .fill #0
LEFTTURNTEMP4 .fill #0
LEFTTURNTEMP6 .fill #0
LEFTTURNTEMP7 .fill #0
; end of TAKEALEFTTURN subroutine
; SUBROUTINE
TAKEARIGHTTURN
; turns the ant 90 degrees right
; INPUT R1: address in memory of ANT
; LOCAL R2: ant
; R3: bitmask
; R4: 3rdbit
; R5: 2nd and 3rd bit
; R6:
; R7:
; R0:
st r2, RIGHTTURNTEMP2
st r3, RIGHTTURNTEMP3
st r4, RIGHTTURNTEMP4
st r6, RIGHTTURNTEMP6
st r7, RIGHTTURNTEMP7 ; store r7, load before RET
ldr r2, r1, #0 ; load ant into r2
ld r3, EAST
and r4, r2, r3 ; r4 = 3rdbit
;ld r3, WEST
;and r5, r2, r3 ; r5 = 2nd and 3rd bits
add r4, r4, #0 ; check if 3rd bit is 0
brnp THIRDBIT1RIGHT ; If so, continue. If not, jump to next part.
; 3rd bit is 0, so XOR r2 ant-word with EAST bitmask
ld r3, EAST
BRNZP RIGHTTURNEND
THIRDBIT1RIGHT
; third bit is 1, so use WEST bitmask
ld r3, WEST
RIGHTTURNEND
add r0, r4, #0 ; move r4 3rdbit into r0 temporarily
add r4, r3, #0 ; move r3 bitmask into r4 for the XOR subroutine
JSR FAKEXOR ; r6 = r2 XOR r4
; flips the correct bit to turn right
add r3, r4, #0 ; moves r4 bitmask back into r3
add r4, r0, #0 ; moves r0 3rdbit back into r3
str r6, r1, #0 ; store modified ant-word with new direction back in memory
ld r2, RIGHTTURNTEMP2
ld r3, RIGHTTURNTEMP3
ld r4, RIGHTTURNTEMP4
ld r6, RIGHTTURNTEMP6
ld r7, RIGHTTURNTEMP7
RET
RIGHTTURNTEMP2 .fill #0
RIGHTTURNTEMP3 .fill #0
RIGHTTURNTEMP4 .fill #0
RIGHTTURNTEMP6 .fill #0
RIGHTTURNTEMP7 .fill #0
; end of TAKEARIGHTTURN subroutine
; SUBROUTINE
ANTCOORDS
; INPUT r2: index of ant
; OUTPUT r1: x coordinate value
; r3: y coordinate value
; "Enter x coordinates for ant #whatever"
st r4, COORD2
ld r0, NEWLINE
out
lea r0, ENTERXCOORDS
puts
ld r3, ASCIIPLUS
;add r0, r2, r3
;out
ld r0, NEWLINE
out
ld r5, ASCIIDIFF
getc
out
add r4, r0, r5 ; r4 holds first digit of x
add r1, r4, r4 ; r1 = 2 * r4
add r1, r1, r1 ; r1 = 4 * r4
add r1, r1, r1 ; r1 = 8 * r4
add r1, r1, r4 ; r1 = 9 * r4
add r1, r1, r4 ; r1 = 10 * r4
getc
out
add r4, r0, r5 ; r4 holds 2nd digit of x
add r1, r1, r4 ; full value of x coordt
st r1, COORD1
; "enter y coords"
ld r0, NEWLINE
out
lea r0, ENTERYCOORDS
puts
ld r3, ASCIIPLUS
;add r0, r2, r3
;out
ld r0, NEWLINE
out
ld r5, ASCIIDIFF
getc
out
add r4, r0, r5 ; r4 holds first digit of y
add r1, r4, r4 ; r1 = 2 * r4
add r1, r1, r1 ; r1 = 4 * r4
add r1, r1, r1 ; r1 = 8 * r4
add r1, r1, r4 ; r1 = 9 * r4
add r1, r1, r4 ; r1 = 10 * r4
getc
out
add r4, r0, r5 ; r4 holds 2nd digit of y
add r3, r1, r4 ; full value of y coord
ld r1, COORD1
ld r4, COORD2
RET
ENTERXCOORDS .STRINGZ "Enter x coordinates for ant "
ENTERYCOORDS .STRINGZ "Enter y coordinates for ant "
ASCIIDIFF .fill #-48
ASCIIPLUS .fill #48
COORD1 .fill #0
NEWLINE .fill #10
COORD2 .fill #0
COORD3 .fill #0
; END OF ANT_COORDINATES_SUBROUTINE
MAPPY
; Maps the coordinates of the ant
; Input: R1: x coord
; R3: y coord
; R4: grid size
; Output: R5: Cell ID
; Cell ID = grid size * y coord + x coord
st r6, MAP1
st r7, MAP2
; multiply by 100
add R0, R3, R3 ; 2y
add R0, R0, R0 ; 4y
add R6, R0, R0 ; 8y
add R6, R6, R6 ; 16y
add R6, R6, R6 ; 32y
add R0, R0, R6 ; 36y
add R6, R6, R6 ; 64y
add R0, R0, R6 ; 100y
ld R7, N100a
add R7, R4, R7
brz GRID100a
add R0, R0, R0 ;200y
add R0, R0, R3 ;300y
GRID100a
Add R5, R0, R1 ; OUTPUT: R5 = grid*y + x
ld r6, MAP1
ld r7, MAP2
RET
N100a .fill #-100
MAP1 .fill #0
MAP2 .fill #0
; END OF MAPPY SUBROUTINE
.end
</syntaxhighlight>
=={{header|Liberty BASIC}}==
Native graphics.
[[Image:langtonsant.png]]
<syntaxhighlight lang="lb">dim arena(100,100)
black=0
white=not(black)
for i = 1 to 100
for j = 1 to 100
arena(i,j)=white
next
next
'north=1 east=2 south=3 west=4
nomainwin
graphicbox #1.g, 0, 0, 100, 100
open "Langton's Ant" for window as #1
#1 "trapclose Quit"
#1.g "down"
antX=50:antY=50
nsew=1 'ant initially points north
while (antX>0) and (antX<100) and (antY>0) and (antY<100)
if arena(antX,antY) then
nsew=nsew-1
if nsew<1 then nsew=4
else
nsew=nsew+1
if nsew>4 then nsew=1
end if
select case nsew
case 1: antY=antY-1
case 2: antX=antX+1
case 3: antY=antY+1
case 4: antX=antX-1
end select
arena(antX,antY)=not(arena(antX,antY))
#1.g "color ";GetColor$(antX,antY)
#1.g "set ";antX;" ";antY
wend
#1.g "flush"
wait
function GetColor$(x,y)
if arena(x,y) then
GetColor$="white"
else
GetColor$="black"
end if
end function
sub Quit handle$
close #handle$
end
end sub
</syntaxhighlight>
Text version.
<syntaxhighlight lang="lb">
'move up=1 right=2 down=3 left=4
' ---------------------------------
dim plane(100,100)
x = 50: y = 50
mx = 100
while (x>0) and (x<100) and (y>0) and (y<100)
if plane(x,y) then
nxt = nxt - 1
if nxt < 1 then nxt = 4
else
nxt = nxt + 1
if nxt > 4 then nxt = 1
end if
x = x + (nxt = 2) - (nxt = 4)
y = y + (nxt = 3) - (nxt = 1)
plane(x,y) = (plane(x,y) <> 1)
mx = min(x,mx)
wend
for x = mx to 100
for y = 1 to 100
print chr$((plane(x,y)*3) + 32);
next y
print x
next x
</syntaxhighlight>
=={{header|Locomotive Basic}}==
<syntaxhighlight lang="locobasic">10 mode 1:defint a-z:deg
20 ink 1,0:ink 0,26
30 x=50:y=50:ang=270
40 dim play(100,100)
50 graphics pen 3:move 220,100:drawr 200,0:drawr 0,200:drawr -200,0:drawr 0,-200
60 ' move ant
70 if play(x,y) then ang=ang-90 else ang=ang+90
80 play(x,y)=1-play(x,y)
90 plot 220+2*x,100+2*y,play(x,y)
100 ang=ang mod 360
110 x=x+sin(ang)
120 y=y+cos(ang)
130 if x<1 or x>100 or y<1 or y>100 then end
140 goto 70</syntaxhighlight>
Output:
[[File:Langtons Ant Locomotive BASIC.png]]
=={{header|Logo}}==
<syntaxhighlight lang="logo">make "size 100
make "white 1
make "black 2
make "sum sum :white :black
make "chars [. #]
make "origin quotient :size 2
make "grid mdarray (list :size :size)
make "directions [ [1 0] [0 1] [-1 0] [0 -1] ]
repeat size [
local "y
make "y repcount
repeat size [
mdsetitem (list repcount :y) :grid :white
]
]
make "x quotient :size 2
make "y quotient :size 2
make "direction sum 1 random count :directions
while [(and (:x > 0) (:x <= :size) (:y > 0) (:y <= :size))] [
local "color
make "color mditem (list :x :y) :grid
local "delta
ifelse [equal? :color :white] [
make "delta 1
] [
make "delta -1
]
make "direction sum 1 (modulo (:direction + :delta - 1) count :directions)
make "dir (item :direction :directions)
mdsetitem (list :x :y) :grid (sum :sum minus :color)
make "x sum :x first :dir
make "y sum :y last :dir
]
repeat size [
local "y
local "blank
make "y repcount
make "blank "true
repeat size [if ( (mditem (list repcount :y) :grid) = :black ) [make "blank "false]]
if [not :blank] [
repeat size [
type item (mditem (list repcount :y) :grid) :chars
]
print []
]
]
bye</syntaxhighlight>
{{Output}}
<pre>...............................................................................................##...
..............................................................................................####..
.............................................................................................#.##.#.
............................................................................................##.####.
...........................................................................................#.#.#.#.#
..........................................................................................##..#.###.
.............................##..........................................................#.#..###..#
......................##......##........................................................##..#...###.
.....................#..#..#.##.#......................................................#.#..###..#..
....................###..###.#..#.....................................................##..#...###...
....................#.####..##.#.....................................................#.#..###..#....
............................##......................................................##..#...###.....
......................##.##.##.....................................................#.#..###..#......
......................####..#.##.#................................................##..#...###.......
......................#####.##.###.##....##....##................................#.#..###..#........
.......................#..#.#.##.#..##....####..##..............................##..#...###.........
........................####.###.####....####..##.#............................#.#..###..#..........
........................###.#...#....##..##.......#...##......................##..#...###...........
.........................####.##...##..##..#......#..#..#....................#.#..###..#............
.........................#.##..#..#...##.##.......#...#..#..................##..#...###.............
.........................#.####..##.#.#.########.#....#..#.................#.#..###..#..............
.........................##..##..#..##.#.#.##.##....#.#.#.##..##..........##..#...###...............
.........................#.#..#..#..#.#....#...#.##...##..#.#####........#.#..###..#................
...........................##.####.##...#..####...#..#...##...##.#......##..#...###.................
.......................##...##########...##.#####..#.####...#....#.....#.#..###..#..................
.......................#..#..#.##..#..#...#.#..##.#####.##.#.....#....##..#...###...................
.......................#...##....#.##..#.#.....#####.#.#####.....#...#.#..###..#....................
......................#...##...###.###....#.#.##.#.##.######.#..#...##..#...###.....................
......................#.####..##.#..#...###.###.##.##...##.#..##...#.#..###..#......................
.......................##..#....##..#..#########..##..####.#......##..#...###.......................
.......................#....#....#..####..#.###########..##...#..#.#..###..#........................
......................#......#...####.####.......##...#.##..###.##..#...###.........................
......................#...#....#.#.#...##......##.#.#.###.#..#.#.#..###..#..........................
.......................#...##.####..####.#####..##..##.#.##.#.....#...###...........................
........................##..#..#.##.###......#..###.#..#....##.#..###..#............................
..........................#.....#..###.##.#..##.####.#.#..#.#...#...###.............................
.........................#...####.##..#....#..###...##.##...##..###..#..............................
.........................#.##..##.###...#.....##..#..###.##.#.#...###...............................
..........................##.....#.##.....##..#...##.##.........#..#................................
...........................##.#....####..#.#...#...###.##.#...#.#...................................
.............................##.###.#####...#.##.##.##.#.#.##.#.###.#...............................
............................#...#.###.#.######.##.##..####.#...##.###...............................
............................#.#.#.###...#..####..#.#.#####...#.....#................................
.............................###...###.....#.#.###..##.#..##.###.#..................................
..............................##..##.#..#.#...##.####.##..###..#.#..................................
..................................###..##.##.....#.....#...#..#.###.................................
..................................#.......###.........#.#.##..##....................................
....................................#....#..#.........#..#.#........................................
....................................#.##............##...###........................................
.....................................##..#..........####..#.........................................
......................................##..############..##..........................................
</pre>
=={{header|LOLCODE}}==
<syntaxhighlight lang="lolcode">HAI 1.3
I HAS A plane ITZ A BUKKIT
IM IN YR init UPPIN YR i TIL BOTH SAEM i AN 10000
plane HAS A SRS i ITZ FAIL
IM OUTTA YR init
I HAS A x ITZ 50, I HAS A y ITZ 50
I HAS A dir ITZ 0, I HAS A pos, I HAS A cell
BTW, WE PURRTIND WE HAS A 2D STRUKSHUR FUR EZ AKSESS
IM IN YR walker
pos R SUM OF PRODUKT OF y AN 100 AN x
cell R NOT plane'Z SRS pos
plane'Z SRS pos R cell
dir R MOD OF SUM OF dir AN SUM OF 5 AN PRODUKT OF cell AN 2 AN 4
dir, WTF?
OMG 0, x R SUM OF x AN 1, GTFO
OMG 1, y R DIFF OF y AN 1, GTFO
OMG 2, x R DIFF OF x AN 1, GTFO
OMG 3, y R SUM OF y AN 1, GTFO
OIC
BTW, CHEKIN TEH ANTZ BOUNDZ
WON OF BOTH SAEM x AN -1 AN BOTH SAEM x AN 100, O RLY?, YA RLY, GTFO, OIC
WON OF BOTH SAEM y AN -1 AN BOTH SAEM y AN 100, O RLY?, YA RLY, GTFO, OIC
IM OUTTA YR walker
IM IN YR printer UPPIN YR cell TIL BOTH SAEM cell AN 10000
plane'Z SRS cell, O RLY?
YA RLY, VISIBLE "#"!
NO WAI, VISIBLE "."!
OIC
NOT MOD OF SUM OF cell AN 1 AN 100, O RLY?, YA RLY, VISIBLE "", OIC
IM OUTTA YR printer BTW, UR OUTTA CYAN
KTHXBYE</syntaxhighlight>
=={{header|Lua}}==
For this example, the lua Socket and Curses modules and a terminal with enough lines are needed.
<syntaxhighlight lang="lua">local socket = require 'socket' -- needed for socket.sleep
local curses = require 'curses' -- used for graphics
local naptime = 0.02 -- seconds
local world_x, world_y = 100, 100
local world = (function (x, y)
local wrl = {}
for i = 1, y do
wrl[i] = {}
for j = 1, x do
wrl[i][j] = 0
end
end
return wrl
end)(world_x, world_y)
-- directions: 0 up, clockwise
local ant = {
x = math.floor(world_x / 2),
y = math.floor(world_y / 2),
dir = 0,
step = function(self)
if self.dir == 0 then self.y = self.y - 1
elseif self.dir == 1 then self.x = self.x + 1
elseif self.dir == 2 then self.y = self.y + 1
else self.x = self.x - 1
end
end
}
world.step = function (self, ant)
if self[ant.y][ant.x] == 0 then -- white
-- change cell color
self[ant.y][ant.x] = 1
-- change dir
ant.dir = (ant.dir + 1) % 4
ant:step()
-- boundary conditions
if ant.x < 1 then ant.x = world_x
elseif ant.x > world_x then ant.x = 1
end
if ant.y < 1 then ant.y = world_y
elseif ant.y > world_y then ant.y = 1
end
else
-- change cell color
self[ant.y][ant.x] = 0
-- change dir
ant.dir = (ant.dir - 1) % 4
ant:step()
-- boundary conditions
if ant.x < 1 then ant.x = world_x
elseif ant.x > world_x then ant.x = 1
end
if ant.y < 1 then ant.y = world_y
elseif ant.y > world_y then ant.y = 1
end
end
end
world.draw = function (self, ant)
for i = 1, #self do
for j = 1, #self[i] do
if i == ant.y and j == ant.x then
win:attron(curses.color_pair(3))
win:mvaddch(i,j,"A")
--win:attroff(curses.color_pair(3))
elseif self[i][j] == 0 then
win:attron(curses.color_pair(1))
win:mvaddch(i,j," ")
--win:attroff(curses.color_pair(1))
elseif self[i][j] == 1 then
win:attron(curses.color_pair(2))
win:mvaddch(i,j," ")
--win:attroff(curses.color_pair(2))
else error("self[" .. i .. "][" .. j .. "] is " .. self[i][j] .. "!")
end
end
end
end
local it = 1
curses.initscr()
curses.start_color()
curses.echo(false)
curses.init_pair(1, curses.COLOR_WHITE, curses.COLOR_WHITE)
curses.init_pair(2, curses.COLOR_BLACK, curses.COLOR_BLACK)
curses.init_pair(3, curses.COLOR_RED, curses.COLOR_WHITE)
curses.init_pair(4, curses.COLOR_WHITE, curses.COLOR_BLACK)
win = curses.newwin(world_y + 1, world_x, 0, 0)
win:clear()
repeat
world:draw(ant)
win:move(world_y, 0)
win:clrtoeol()
win:attron(curses.color_pair(4))
win:addstr("Iteration: " .. it .. ", nap = " .. naptime*1000 .. "ms")
win:refresh()
world:step(ant)
it = it + 1
--local c = stdscr:getch()
--if c == '+' then naptime = naptime - (naptime / 10)
--elseif c == '-' then naptime = naptime + (naptime / 10)
--end
socket.sleep(naptime)
until false
</syntaxhighlight>
=={{header|M2000 Interpreter}}==
<syntaxhighlight lang="m2000 interpreter">
Module Ant {
Form 120,102
N=100
Enum CellColor {black=0,white=#FFFFFF}
Enum Direction{North=90, West=180, South=270, East=0}
Function Rotate(cd as Direction, clockwise=true) {
cd=(cd+if(clockwise->270,90)) mod 360
=cd ' return a Direction Enum type
}
dim rect(1 to N, 1 to N)=white
cx=N div 2
cy=N div 2
cd=North
rect(cx,cy)=black
endmove=False
while not endmove
movecell()
end while
Disp()
sub movecell()
select case rect(cx,cy)
case black
cd=Rotate(cd, false) : rect(cx, cy)=white
case white
cd=Rotate(cd) : rect(cx, cy)=black
end select
select case cd
case North
cy--
case West
cx--
case South
cy++
case East
cx++
end select
endmove= cx<1 or cx>N or cy<1 or cy>N
end sub
sub disp()
Local Doc$, i, j
Document Doc$
for i=1 to N:for j=1 to N
Doc$=if$(rect(j,i)=White->"_","#")
next
Doc$={
}
next
cls
Print #-2,Doc$
clipboard Doc$
end sub
}
Ant
</syntaxhighlight>
{{out}}
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</pre >
=={{header|make}}==
[[File:make_langton_ant.png|right]]
<syntaxhighlight lang="make"># Langton's ant Makefile
# netpbm is an ancient collection of picture file formats
# convert and display are from imagemagick
.PHONY: display
display: ant.png
display $<
ant.png: ant.pbm
convert $< $@
n9:=1 2 3 4 5 6 7 8 9
n100:=$(n9) $(foreach i,$(n9),$(foreach j,0 $(n9),$i$j)) 100
ndec:=0 $(n100)
ninc:=$(wordlist 2,99,$(n100))
$(foreach i,$(n100),$(eval row$i:=$(foreach j,$(n100),0)))
.PHONY: $(foreach i,$(ndec),row$i)
row0:
@echo >ant.pbm P1
@echo >>ant.pbm '#' Langton"'"s ant
@echo >>ant.pbm 100 100
rowrule=row$i: row$(word $i,$(ndec)); @echo >>ant.pbm $$($$@)
$(foreach i,$(n100),$(eval $(rowrule)))
ant.pbm: Makefile row100
@:
x:=50
y:=50
direction:=1
turn=$(eval direction:=$(t$(xy)$(direction)))
xy=$(word $x,$(row$y))
t01:=4
t02:=1
t03:=2
t04:=3
t11:=2
t12:=3
t13:=4
t14:=1
flip=$(eval row$y:=$(start) $(not$(xy)) $(end))
start=$(wordlist 1,$(word $x,$(ndec)),$(row$y))
not0:=1
not1:=0
end=$(wordlist $(word $x,$(ninc) 100),100,$(row$y))
step=$(eval $(step$(direction)))
step1=y:=$(word $y,exit $(n100))
step2=x:=$(word $x,$(ninc) exit)
step3=y:=$(word $y,$(ninc) exit)
step4=x:=$(word $x,exit $(n100))
iteration=$(if $(filter exit,$x $y),,$(turn)$(flip)$(step))
$(foreach i,$(n100) $(n100),$(foreach j,$(n100),$(iteration)))
</syntaxhighlight>
=={{header|Mathematica}}/{{header|Wolfram Language}}==
[[File:LangtonsAnt.png|right|thumb|Output]]
<syntaxhighlight lang="mathematica">direction = 1;
data = SparseArray[{{50, 50} -> -1}, {100, 100}, 1];
NestWhile[
{Re@#, Im@#} &@(direction *= (data[[Sequence @@ #]] *= -1) I) + # &,
{50, 50}, 1 <= Min@# <= Max@# <= 100 &];
Image@data</syntaxhighlight>
=={{header|MATLAB}} / {{header|Octave}}==
<syntaxhighlight lang="matlab">function u = langton_ant(n)
if nargin<1, n=100; end;
A = sparse(n,n); % white
P = [n/2;n/2]; % Positon
D = 3; % index of direction 0-3
T = [1,0,-1,0;0,1,0,-1]; % 4 directions
k = 0;
while (1)
k = k+1;
a = A(P(1),P(2));
A(P(1),P(2)) = ~a;
if ( a )
D = mod(D+1,4);
else
D = mod(D-1,4);
end;
P = P+T(:,D+1);
if (~mod(k,100)),spy(A);pause(.1);end; %display after every 100 interations
end;
end</syntaxhighlight>
=={{header|Nim}}==
{{trans|Python}}
<syntaxhighlight lang="nim">import strutils, sequtils
type
Direction = enum up, right, down, left
Color = enum white, black
const
width = 75
height = 52
maxSteps = 12_000
var
m: array[height, array[width, Color]]
dir = up
x = width div 2
y = height div 2
var i = 0
while i < maxSteps and x in 0 ..< width and y in 0 ..< height:
let turn = m[y][x] == black
m[y][x] = if m[y][x] == black: white else: black
dir = Direction((4 + int(dir) + (if turn: 1 else: -1)) mod 4)
case dir
of up: dec y
of right: dec x
of down: inc y
of left: inc x
inc i
for row in m:
echo map(row, proc(x: Color): string =
if x == white: "." else: "#").join("")</syntaxhighlight>
=={{header|OCaml}}==
<
type dir = North | East | South | West
Line 1,306 ⟶ 6,240:
if not(key_pressed()) then loop (move pos dir) dir
in
loop (size_x()/2, size_y()/2) North</
Run with:
$ ocaml graphics.cma langton.ml
=={{header|Octave}}==
<syntaxhighlight lang="octave">clear
E=100 % Size of lattice.
N=11200 % Number of iterations.
z(1:1:E^2)=-1; % Init lattice rotations (-1=right, 1=left)
k(1:1:E^2)=0;
k(1)=(E^2+E)/2; % Init the Ant @ 50,50
for t=1:1:N;
k(t+1)=mod(k(t)+real(round((0.5*(E+1)*exp(i*pi/4*(trace(diag(z))-E^2)))-(0.5*(E-1)*exp(-i*pi/4*(trace(diag(z))-E^2)))))+imag(round((0.5*(E+1)*exp(i*pi/4*(trace(diag(z))-E^2)))-(0.5*(E-1)*exp(-i*pi/4*(trace(diag(z))-E^2))))),E^2);
z(k(t+1)+1)=real(exp(2*i*pi/4*(1+z(k(t+1)+1))));
endfor;
imagesc(reshape(z,E,E)) % Draw the Lattice
</syntaxhighlight>
=={{header|Ol}}==
{{libheader|OpenGL}}
<syntaxhighlight lang="scheme">
#!/usr/bin/ol
(import (otus random!))
(define MAX 65536) ; should be power of two
; size of game board (should be less than MAX)
(define WIDTH 170)
(define HEIGHT 96)
; helper function
(define (hash x y)
(let ((x (mod (+ x WIDTH) WIDTH))
(y (mod (+ y HEIGHT) HEIGHT)))
(+ (* y MAX) x)))
;; ; helper function
(define directions '(
(0 . 1) (1 . 0) (0 . -1) (-1 . 0)
))
; ---------------
(import (lib gl2))
(gl:set-window-title "Langton's Ant")
(glShadeModel GL_SMOOTH)
(glClearColor 0.11 0.11 0.11 1)
(glOrtho 0 WIDTH 0 HEIGHT 0 1)
(glPointSize (/ 854 WIDTH))
; generate random field
(gl:set-userdata
(list->ff (map (lambda (i) (let ((x (rand! WIDTH)) (y (rand! HEIGHT)))
(cons (hash x y) #t))) (iota 1000))))
(define ant (cons
(rand! WIDTH)
(rand! HEIGHT)))
(define dir (list (rand! 4))) ; 0, 1, 2, 3
; main game loop
(gl:set-renderer (lambda (mouse)
(let ((generation (gl:get-userdata)))
(glClear GL_COLOR_BUFFER_BIT)
; draw the cells
(glColor3f 0.2 0.5 0.2)
(glBegin GL_POINTS)
(ff-fold (lambda (st key value)
(glVertex2f (mod key MAX)
(div key MAX))
) #f generation)
(glColor3f 0.8 0.2 0.1)
(glVertex2f (car ant) (cdr ant))
(glEnd)
(gl:set-userdata
(let*((x (car ant))
(y (cdr ant))
(generation (case (get generation (hash x y) #f)
(#true ; black cell
(set-car! dir (mod (+ (car dir) 1) 4))
(del generation (hash x y)))
(#false
(set-car! dir (mod (+ (car dir) 7) 4))
(put generation (hash x y) #true)))))
(set-car! ant (mod (+ x (car (lref directions (car dir)))) WIDTH))
(set-cdr! ant (mod (+ y (cdr (lref directions (car dir)))) HEIGHT))
generation))
)))
</syntaxhighlight>
=={{header|PARI/GP}}==
[[File:Langton-pari.png|right|thumb]]
<
my(M=matrix(100,100),x=50,y=50,d=0);
while(x && y && x<=100 && y<=100,
Line 1,327 ⟶ 6,351:
plothraw(u,v)
};
show(langton())</
=={{header|Pascal}}==
Pascal does not offer complex number arithmetic, so adjusting directions via multiplication of ±i is out. Similarly, it does not offer array manipulation statements, so <code>Cell:=White;</code> must be achieved via explicit for-loops with explicitly stated indices and bounds, and the adjustment of the (x,y) position by (dx,dy) can't be done by array addition. Otherwise, matters are straightforward, so instead this version tries to animate the ant on the screen. Alas, the maximum screen size is 80 characters by 50 lines, except that output to the last line causes a screen scroll so that only 49 lines are available. Alas, this cell array is too small and the bounds are exceeded in step 5,156 - before the ant starts its migration.
The animation shows the arrival at a cell with a yellow arrow pointing in the arrival direction. The cell state is investigated to decide the new direction (which is shown as a green arrow), the current cell's state is flipped, and the move to the new cell position is made. To show these events, the programme waits for a keystroke but if the S key is pressed, full speed results. Each stepwise ant move thus requires two keystrokes (one for each of the two directions being shown) however a quirk of Pascal's processing of keyboard symbols has certain keystrokes represented via ''two'' values from ReadKey, so pressing the arrow keys for example provides a doubled advance.
{{works with| Free Pascal}}
{{works with|Turbo Pascal}} Except, the green arrow on step 4 does not appear!
<syntaxhighlight lang="pascal">
{$B- Early and safe resolution of If x <> 0 and 1/x...}
Program LangtonsAnt; Uses CRT;
{Perpetrated by R.N.McLean (whom God preserve), Victoria University, December MMXV.}
Var AsItWas: record mode: word; ta: word; end;
Var LastLine,LastCol: byte;
Procedure Swap(var a,b: integer); {Oh for a compiler-recognised statement.}
var t: integer; {Such as A=:=B;}
Begin
t:=a; a:=b; b:=t;
End;
var Stepwise: boolean;
Var Cell: Array[1..80,1..50] of byte; {The screen is of limited size, alas.}
Var x,y,Step: integer; {In the absence of complex numbers,}
Var dx,dy: integer; {And also of array action statements.}
Procedure Croak(Gasp: string); {Exit message...}
Begin
GoToXY(1,12); TextColor(Yellow); {Reserve line twelve.}
WriteLn(Gasp,' on step ',Step,' to (',x,',',y,')');
HALT;
End;
Procedure Harken; {Waits for a keystroke.}
var ch: char; {The character. Should really be 16-bit.}
Begin
ch:=ReadKey; {Fancy keys evoke double characters. I don't care.}
if (ch = 'S') or (ch = 's') then Stepwise:=not Stepwise {Quick, slow, quick, quick, slow...}
else if ch = #27 then Croak('ESC!'); {Or perhaps, enough already!}
End; {Fancy keys will give a twostep.}
Procedure Waitabit; {Slows the action.}
Begin
if Stepwise or KeyPressed then Harken; {Perhaps a change while on the run.}
End; {of Waitabit.}
Procedure Turn(way:integer); {(dx,dy)*(0,w) = (-w*dy,+w*dx)}
Begin
Swap(dx,dy); {In the absence of complex arithmetic,}
dx:=-way*dx; dy:=way*dy; {Do this in two stages.}
End;
const Arrow: array[-1..+1,-1..+1] of integer {Only four entries are of interest.}
= ((1,27,3),(25,5,24),(7,26,9)); {For the four arrow symbols.}
Procedure ShowDirection(Enter,How: byte); {Show one.}
Begin
GoToXY(x,LastLine - y + 1); {(x,y) position, in Cartesian style.}
TextBackground(Enter); {The value in Cell[x,y] may have been changed.}
TextColor(How);
Writeln(chr(Arrow[dx,dy])); {Not an ASCII control character, but an arrow symbol.}
Waitabit; {Having gone to all this trouble.}
End;
Procedure ShowState; {Special usage for line two of the screen.}
Begin
GoToXY(1,2); TextBackground(LightGray); TextColor(Black);
Write(Step:5,' (',x:2,',',y:2,') ');
TextColor(Yellow); {Yellow indicates the direction in mind.}
Write(chr(Arrow[dx,dy])); {On *arrival* at a position.}
End;
Var i,j: integer; {Steppers. No whole-array assault as in Cell:=LightGray;}
var Enter: byte; {Needed to remember the cell state on arrival.}
BEGIN
AsItWas.mode:=LastMode; {Grr. I might want to save the display content too!}
AsItWas.ta:=TextAttr; {Not just its colour and style.}
TextMode(C80+Font8x8); {Crazed gibberish gives less unsquare character cells, and 80x50 of them.}
LastLine:=Hi(WindMax); { + 1 omitted, as a write to the last line scrolls the screen up one...}
LastCol:=Lo(WindMax) + 1; {Counting starts at zero, even though GoToXY starts with one.}
x:=LastCol div 2; {Start somewhere middleish.}
y:=LastLine div 2; {Consider (x,y) as being (0,0) for axes.}
dx:=+1; dy:=0; {Initial direction.}
TextBackground(LightGray); {"White" is not valid for background colour.}
TextColor(Black); {This will show up on a light background.}
ClrScr; {Here we go.}
WriteLn('Langton''s Ant, on x = 1:',LastCol,', y = 1:',LastLine);
ShowState; {Where we start.}
WriteLn; TextColor(Black);
WriteLn('Press a key for each step.'); {Some encouragement.}
WriteLn('"S" to pause each step or not.');
WriteLn('ESC to quit.');
for i:=1 to LastLine do begin GoToXY(x,i); Write('|'); end; {Draw a y-axis.}
for i:=1 to LastCol do begin GoToXY(i,LastLine - y + 1); Write('-'); end; {And x.}
gotoxy(1,6); {Can't silence the cursor!}
for i:=1 to LastCol do {Prepare the cells.}
for j:=1 to LastLine do {One by one.}
Cell[i,j]:=LightGray; {Cell:=LightGray. Sigh.}
Stepwise:=true; {The action is of interest.}
for Step:=1 to 12000 do {Here we go.}
if (x <= 0) or (x > LastCol) or (y <= 0) or (y > LastCol) then Croak('Out of bounds')
else {We're in a cell.}
begin {So, inspect it.}
if Stepwise or (Step mod 10 = 0) then ShowState {On arrival.}
else if KeyPressed then Harken; {If we're not pausing, check for a key poke.}
Enter:=cell[x,y]; {This is what awaits the feet.}
if Stepwise then ShowDirection(Enter,Yellow); {Current direction, about to be changed.}
case cell[x,y] of {So, what to do?}
LightGray: begin Cell[x,y]:=Black; Turn(-1); end;{White. Make black and turn right.}
Black: begin Cell[x,y]:=LightGray; Turn(+1); end;{Black. Make white and turn left.}
end; {Having decided,}
if Stepwise then ShowDirection(Enter,Green); {Show the direction about to be stepped.}
GoToXY(x,LastLine - y + 1); {Screen location (column,line) for (x,y)}
TextBackground(Cell[x,y]); {Change the state I'm about to leave.}
Write(' '); {Foreground colour irrelevant for spaces.}
x:=x + dx; y:=y + dy; {Make the step!}
end; {On to consider our new position.}
Croak('Finished'); {That was fun.}
END.
</syntaxhighlight>
=={{header|Perl}}==
<
use strict;
# Perl 5 implementation of Langton's Ant
# Using screen coordinates - 0,0 in upper-left, +X right, +Y down -
# these directions (right, up, left, down) are counterclockwise
# so advance through the array to turn left, retreat to turn right
my @dirs = ( [1,0], [0,-1], [-1,0], [0,1] );
my $size = 100;
# we treat any false as white and true as black, so undef is fine for initial all-white grid
my @plane;
for (0..$size-1) { $plane[$_] = [] };
# start out in approximate middle
my ($x, $y) = ($size/2, $size/2);
# pointing in a random direction
my $dir = int rand @dirs;
my $move;
for ($move = 0; $x >= 0 && $x < $size && $y >= 0 && $y < $size; $move++) {
# toggle cell's value (white->black or black->white)
if ($plane[$x][$y] = 1 - ($plane[$x][$y] ||= 0)) {
# if it's now true (black), then it was white, so turn right
$dir = ($dir - 1) % @dirs;
} else {
# otherwise it was black, so turn left
$dir = ($dir + 1) % @dirs;
}
$x += $dirs[$dir][0];
$y += $dirs[$dir][1];
}
print "Out of bounds after $move moves at ($x, $y)\n";
for (my $y=0; $y<$size; ++$y) {
Line 1,354 ⟶ 6,518:
}
print "\n";
}</
=={{header|
<!--<syntaxhighlight lang="phix">(phixonline)-->
<span style="color: #004080;">sequence</span> <span style="color: #000000;">grid</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">repeat</span><span style="color: #0000FF;">(</span><span style="color: #008000;">' '</span><span style="color: #0000FF;">,</span><span style="color: #000000;">100</span><span style="color: #0000FF;">),</span><span style="color: #000000;">100</span><span style="color: #0000FF;">)</span>
<span style="color: #004080;">integer</span> <span style="color: #000000;">aX</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">50</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">aY</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">50</span><span style="color: #0000FF;">,</span>
<span style="color: #000000;">gXY</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">angle</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span> <span style="color: #000080;font-style:italic;">-- ' '/'#'; 0,1,2,3 = NESW</span>
<span style="color: #008080;">constant</span> <span style="color: #000000;">dX</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,-</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">0</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">}</span> <span style="color: #000080;font-style:italic;">-- (dY = reverse(dX))</span>
<span style="color: #008080;">while</span> <span style="color: #000000;">aX</span><span style="color: #0000FF;">>=</span><span style="color: #000000;">1</span> <span style="color: #008080;">and</span> <span style="color: #000000;">aX</span><span style="color: #0000FF;"><=</span><span style="color: #000000;">100</span>
<span style="color: #008080;">and</span> <span style="color: #000000;">aY</span><span style="color: #0000FF;">>=</span><span style="color: #000000;">1</span> <span style="color: #008080;">and</span> <span style="color: #000000;">aY</span><span style="color: #0000FF;"><=</span><span style="color: #000000;">100</span> <span style="color: #008080;">do</span>
<span style="color: #000000;">gXY</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">grid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">aX</span><span style="color: #0000FF;">][</span><span style="color: #000000;">aY</span><span style="color: #0000FF;">]</span>
<span style="color: #000000;">grid</span><span style="color: #0000FF;">[</span><span style="color: #000000;">aX</span><span style="color: #0000FF;">][</span><span style="color: #000000;">aY</span><span style="color: #0000FF;">]</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">67</span><span style="color: #0000FF;">-</span><span style="color: #000000;">gXY</span> <span style="color: #000080;font-style:italic;">-- ' '<=>'#', aka 32<->35</span>
<span style="color: #000000;">angle</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mod</span><span style="color: #0000FF;">(</span><span style="color: #000000;">angle</span><span style="color: #0000FF;">+</span><span style="color: #000000;">2</span><span style="color: #0000FF;">*</span><span style="color: #000000;">gXY</span><span style="color: #0000FF;">+</span><span style="color: #000000;">3</span><span style="color: #0000FF;">,</span><span style="color: #000000;">4</span><span style="color: #0000FF;">)</span> <span style="color: #000080;font-style:italic;">-- +/-1, ie 0,1,2,3 -> 1,2,3,0 or 3,0,1,2</span>
<span style="color: #000000;">aX</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">dX</span><span style="color: #0000FF;">[</span><span style="color: #000000;">angle</span><span style="color: #0000FF;">+</span><span style="color: #000000;">1</span><span style="color: #0000FF;">]</span>
<span style="color: #000000;">aY</span> <span style="color: #0000FF;">+=</span> <span style="color: #000000;">dX</span><span style="color: #0000FF;">[</span><span style="color: #000000;">4</span><span style="color: #0000FF;">-</span><span style="color: #000000;">angle</span><span style="color: #0000FF;">]</span>
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
<span style="color: #7060A8;">puts</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">join</span><span style="color: #0000FF;">(</span><span style="color: #000000;">grid</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"\n"</span><span style="color: #0000FF;">))</span>
<!--</syntaxhighlight>-->
{{out}}
<pre style="font-size: 2px">
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##
</pre>
=={{header|PHP}}==
[[Image:langtons_ant_php.png|right|100px]]
<br>
''This is an implementation of Langton`s Ant in PHP''<br>
''(The TEXT TO IMAGE - part is obviously not necessary.''<br>
''Additionally the x and y startpositions could be set''<br>
''to the halves of width and height.)''<br>
<br>
<syntaxhighlight lang="php">
// INIT AND DEFINITION
define('dest_name', 'output.png'); // destination image
define('width', 100);
define('height', 100);
$x = 50;
$y = 70;
$dir = 0; // 0-up, 1-left, 2-down, 3-right
$field = array();
$step_count = 0;
// LANGTON´S ANT PROCEDURE
while(0 <= $x && $x <= width && 0 <= $y && $y <= height){
if(isset($field[$x][$y])){
unset($field[$x][$y]);
$dir = ($dir + 3) % 4;
}else{
$field[$x][$y] = true;
$dir = ($dir + 1) % 4;
}
switch($dir){
case 0: $y++; break;
case 1: $x--; break;
case 2: $y--; break;
case 3: $x++; break;
}
$step_count++;
}
// ARRAY TO IMAGE
$img = imagecreatetruecolor(width, height);
$white = imagecolorallocate($img, 255, 255, 255);
for($x = 0; $x < width; $x++){
for($y = 0; $y < height; $y++){
if(isset($field[$x][$y])){
imagesetpixel($img, $x, $y, $white);
}
}
}
// TEXT TO IMAGE
$color = array();
$color[0] = imagecolorallocate($img, 255, 0, 0);
$color[1] = imagecolorallocate($img, 0, 255, 0);
$color[2] = imagecolorallocate($img, 0, 0, 255);
$print_array = array(
0 => 'Langton`s Ant', 1=>'PHP Version', 2=>'Steps: ' . $step_count
);
foreach($print_array as $key => $line){
imagestring($img, 3, 3, 3 + $key*11, $line, $color[$key]);
}
// SAVE IMAGE
imagepng($img, dest_name);
</syntaxhighlight>
=={{header|PicoLisp}}==
[[File:Picolisp_ant.gif|right|thumb]]
This code pipes a PBM into ImageMagick's "display" to show the result:
<
(let (Field (make (do Height (link (need Width)))) Dir 0)
(until (or (le0 X) (le0 Y) (> X Width) (> Y Height))
Line 1,449 ⟶ 6,675:
(out '(display -) (ant 100 100 50 50))
(bye)
</syntaxhighlight>
=={{header|PowerShell}}==
{{works with|PowerShell|2}}
To simplify the steps within the loop, -1 and 1 are used to represent the binary state of the spaces in the grid. As neither state is now a default value, to simplify setting the starting states, an array of arrays is used instead of a two dimensional array.
<syntaxhighlight lang="powershell">
$Size = 100
$G = @()
1..$Size | ForEach { $G += ,( @( 1 ) * $Size ) }
$x = $y = $Size / 2
# Direction of next move
$Dx = 1
$Dy = 0
# While we are still on the grid...
While ( $x -ge 0 -and $y -ge 0 -and $x -lt $Size -and $y -lt $Size )
{
# Change direction
$Dx, $Dy = ( $Dy * $G[$x][$y] ), -( $Dx * $G[$x][$y] )
# Change state of current square
$G[$x][$y] = -$G[$x][$y]
# Move forward
$x += $Dx
$y += $Dy
}
# Convert to strings for output
ForEach ( $Row in $G ) { ( $Row | ForEach { ( ' ', '', '#')[$_+1] } ) -join '' }
</syntaxhighlight>
{{out}}
Default PowerShell console colors reverse the colors from black on white to white on dark blue. Most blank lines not included below.
<pre style="height:50ex;overflow:scroll">
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################################### ## # ##### ##### ### ## # ################################
################################### ####### ######### # # ## ###################################
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###################################### ## ########## ## ########################################
####################################### ## ## #########################################
####################################################################################################
</pre>
=={{header|Processing}}==
Processing implementation, this uses two notable features of Processing, first of all, the animation is calculated with the draw() loop, second the drawing on the screen is also used to represent the actual state.
<syntaxhighlight lang="processing">/*
* we use the following conventions:
* directions 0: up, 1:
*
* pixel white: true, black: false
Line 1,492 ⟶ 6,807:
for(int i=0;i<STEP;i++) {
count++;
boolean pix=get(x,y)!=-1; //white =-1
setBool(x,y,pix);
Line 1,515 ⟶ 6,830:
break;
case 1:
x
break;
case 2:
Line 1,521 ⟶ 6,836:
break;
case 3:
x
break;
}
Line 1,534 ⟶ 6,849:
void setBool(int x, int y, boolean white) {
set(x,y,white?#ffffff:#000000);
}</
==={{header|Processing Python mode}}===
<syntaxhighlight lang="python">"""
we use the following conventions:
directions 0: up, 1: left, 2: down: 3: right
pixel white: True, black: False
turn right: True, left: False
"""
# number of iteration steps per frame
# set this to 1 to see a slow animation of each
# step or to 10 or 100 for a faster animation
STEP = 100
count = 0
def setup():
global x, y, direction
# 100x100 is large enough to show the
# corridor after about 10000 cycles
size(100, 100, P2D)
background(255)
x = width / 2
y = height / 2
direction = 0
def draw():
global count
for i in range(STEP):
count += 1
pix = get(x, y) != -1 # white =-1
setBool(x, y, pix)
turn(pix)
move()
if (x < 0 or y < 0 or x >= width or y >= height):
println("finished")
noLoop()
break
if count % 1000 == 0:
println("iteration {}".format(count))
def move():
global x, y
if direction == 0:
y -= 1
elif direction == 1:
x -= 1
elif direction == 2:
y += 1
elif direction == 3:
x += 1
def turn(rightleft):
global direction
direction += 1 if rightleft else -1
if direction == -1:
direction = 3
if direction == 4:
direction = 0
def setBool(x, y, white):
set(x, y, -1 if white else 0)</syntaxhighlight>
=={{header|Prolog}}==
This sort of problem, when stated in Prolog, reads a bit like a story book. Our main goal (go) succeeds if we can move north from the middle of the 100x100 matrix, and update_win- which outputs the black/1 blocks. The move/3 and direction/3 goals are really quite self explanatory, mirroring the instructions for the task.
{{works with|SWI Prolog|6.2.6 by Jan Wielemaker, University of Amsterdam}}
[[File:ant.jpg|thumb|right|Sample output]]
<syntaxhighlight lang="prolog">%_______________________________________________________________
% Langtons ant.
:-dynamic
black/1.
plot_point(Row, Col) :- % Output a 5x5 black box at R,C
new(C, box(5,5)), X is Col * 5 - 2, Y is Row * 5 - 2,
send(C, colour, colour(black)), send(C, fill_pattern, colour(blue)),
send(C, center(point(X,Y))), send(@win, display, C).
update_win :- % Make a 500x500 window, find all the black points and plot them
new(@win, window('Langtons Ant')),
send(@win, size, size(500,500)), send(@win, open),
black(Row/Col),plot_point(Row,Col),fail.
update_win.
direction(Row, Col, left) :- black(Row/Col), !, retract(black(Row/Col)).
direction(Row, Col, right):- not(black(Row/Col)), !, assert(black(Row/Col)).
move(_, Row,Col) :- (Row < 0; Col < 0; Row > 99; Col > 99), !.
move(north,Row,Col) :-
(direction(Row,Col,left), C is Col - 1, !, move(west, Row, C));
(direction(Row,Col,right), C is Col + 1, !, move(east, Row, C)).
move(south,Row,Col) :-
(direction(Row,Col,right), C is Col - 1, !, move(west, Row, C));
(direction(Row,Col,left), C is Col + 1, !, move(east, Row, C)).
move(east,Row,Col) :-
(direction(Row,Col,right), R is Row + 1, !, move(south, R, Col));
(direction(Row,Col,left), R is Row - 1, !, move(north, R, Col)).
move(west,Row,Col) :-
(direction(Row,Col,left), R is Row + 1, !, move(south, R, Col));
(direction(Row,Col,right), R is Row - 1, !, move(north, R, Col)).
go :- retractall(black(_)), move(north,49,49), update_win.</syntaxhighlight>
=={{header|PureBasic}}==
[[File:PureBasic_Langtons_ant.png|thumb|Sample display of PureBasic solution]]
<
#Black = 0
#planeHeight = 100
Line 1,591 ⟶ 7,014:
Delay(10) ;control animation speed and avoid hogging CPU
Until quit = 1</
Sample output:
<pre>Out of bounds after 11669 steps.</pre>
=={{header|Python}}==
<syntaxhighlight lang="python">
"""Langton's ant implementation."""
from enum import Enum, IntEnum
class Dir(IntEnum):
"""Possible directions."""
RIGHT = 1
DOWN = 2
LEFT = 3
class Color(Enum):
"""Possible colors."""
WHITE = " "
BLACK = "#"
def invert_color(grid, x, y):
"""Invert the color of grid at x, y coordinate."""
if grid[y][x] == Color.BLACK:
grid[y][x] = Color.WHITE
else:
grid[y][x] = Color.BLACK
def next_direction(grid, x, y, direction):
"""Compute next direction according to current position and direction."""
if grid[y][x] == Color.BLACK:
turn_right = False
else:
turn_right = True
direction_index = direction.value
if turn_right:
direction_index = (direction_index + 1) % 4
else:
direction_index = (direction_index - 1) % 4
directions = [Dir.UP, Dir.RIGHT, Dir.DOWN, Dir.LEFT]
direction = directions[direction_index]
return direction
def next_position(x, y, direction):
"""Compute next position according to direction."""
if direction == Dir.UP:
y -= 1
elif direction == Dir.RIGHT:
x -= 1
elif direction == Dir.DOWN:
y += 1
elif direction == Dir.LEFT:
x += 1
return x, y
def print_grid(grid):
"""Display grid."""
print(80 * "#")
print("\n".join("".join(v.value for v in row) for row in grid))
def ant(width, height, max_nb_steps):
"""Langton's ant."""
grid = [[Color.WHITE] * width for _ in range(height)]
x = width // 2
y = height // 2
direction = Dir.UP
i = 0
while i < max_nb_steps and 0 <= x < width and 0 <= y < height:
invert_color(grid, x, y)
direction = next_direction(grid, x, y, direction)
x, y = next_position(x, y, direction)
print_grid(grid)
i += 1
if __name__ == "__main__":
ant(width=75, height=52, max_nb_steps=12000)
</syntaxhighlight>
The output is similar to the basic D version.
=={{header|Quackery}}==
<syntaxhighlight lang="Quackery"> [ stack 50 ] is xpos ( --> s )
[ stack 50 ] is ypos ( --> s )
[ xpos share 0 100 within
ypos share 0 100 within
and ] is inside ( --> b )
[ -1 ypos ] is north ( --> n s )
[ 1 xpos ] is east ( --> n s )
[ 1 ypos ] is south ( --> n s )
[ -1 xpos ] is west ( --> n s )
[ stack 0 ] is heading ( --> s )
[ 1 ] is right ( --> n )
[ -1 ] is left ( --> n )
[ heading take
+ 4 mod
heading put ] is turn ( --> )
[ heading share
[ table
north east south west ]
do tally ] is move ( --> )
[ ypos share peek
xpos share bit & 0 > ] is black? ( [ --> b )
[ ypos share
2dup peek
xpos share bit ~ &
unrot poke ] is white ( [ --> [ )
[ ypos share
2dup peek
xpos share bit |
unrot poke ] is black ( [ --> [ )
[ 50 xpos replace
50 ypos replace
0 heading replace ] is reset ( --> )
[ witheach
[ 100 times
[ dup i^ bit &
iff say "[]"
else say " " ]
cr
drop ] ] is draw ( [ --> )
[ reset
0 100 of
[ inside while
dup black? iff
[ white left ]
else
[ black right ]
turn
move
again ]
draw ] is ant ( --> )</syntaxhighlight>
{{out}}
Surplus whitespace trimmed. Shown at <sup>'''2'''</sup>/<sub>'''3'''</sub> size.
<pre style="font-size:67%">
[][] [][][][][][][][][][][][] [][]
[] [][][][] [] [][]
[][][] [][] [][] []
[] [] [] [] [] []
[][] [][] [] [] [][][] []
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[] [][][] [][] [] [][] [][][] [] [] [][][] [][][]
[] [] [][][][][] [] [] [][][][] [] [][][] [] [] []
[][][] [][] [] [][][][] [][] [][] [][][][][][] [] [][][] [] []
[] [][][] [] [][] [] [] [][] [][] [][] [] [][][][][] [][][] [][]
[] [] [] [][] [][][] [] [] [] [][][][] [] [][]
[] [] [][] [][] [] [][] [][] [] [][]
[][][] [] [] [][] [][][] [] [][] [] [][][] [][] [][] []
[] [][][] [][] [][] [][] [][][] [] [] [][] [][][][] []
[][][] [] [] [] [] [] [][][][] [][] [] [][] [][][] [] []
[] [][][] [] [][] [] [] [][][] [] [][][] [][] [] [] [][]
[][][] [] [] [][] [] [][] [][] [][][][][] [][][][] [][][][] [][] []
[] [][][] [] [] [] [] [][][] [] [] [][] [][] [] [] [] [] []
[][][] [] [][] [][][] [][] [] [][] [][][][] [][][][] [] []
[] [][][] [] [] [] [][] [][][][][][][][][][][] [] [][][][] [] [] []
[][][] [] [][] [] [][][][] [][] [][][][][][][][][] [] [][] [] [][]
[] [][][] [] [] [][] [] [][] [][] [][] [][][] [][][] [] [] [][] [][][][] []
[][][] [] [][] [] [] [][][][][][] [][] [] [][] [] [] [][][] [][][] [][] []
[] [][][] [] [] [] [][][][][] [] [][][][][] [] [] [][] [] [][] []
[][][] [] [][] [] [] [][] [][][][][] [][] [] [] [] [] [][] [] [] []
[] [][][] [] [] [] [] [][][][] [] [][][][][] [][] [][][][][][][][][][] [][]
[][][] [] [][] [] [][] [][] [] [] [][][][] [] [][] [][][][] [][]
[] [][][] [] [] [][][][][] [] [][] [][] [] [] [] [] [] [] [] []
[][][] [] [][] [][] [][] [] [] [] [][] [][] [] [] [][] [] [][] [][]
[] [][][] [] [] [] [] [] [][][][][][][][] [] [] [][] [][][][] []
[][][] [] [][] [] [] [] [][] [][] [] [] [][] []
[] [][][] [] [] [] [] [] [] [][] [][] [][] [][][][]
[][][] [] [][] [][] [] [][] [][] [] [] [][][]
[] [][][] [] [] [] [][] [][][][] [][][][] [][][] [][][][]
[][][] [] [][] [][] [][][][] [][] [] [][] [] [] []
[] [][][] [] [] [][] [][] [][] [][][] [][] [][][][][]
[][][] [] [][] [] [][] [] [][][][]
[] [][][] [] [] [][] [][] [][]
[][][] [] [][] [][]
[] [][][] [] [] [] [][] [][][][] []
[][][] [] [][] [] [] [][][] [][][]
[] [][][] [] [] [] [][] [] [] []
[][][] [] [][] [][] [][]
[] [][][] [] [] [][]
[][][] [] [][]
[] [] [] [] []
[][][][] [][]
[] [][] []
[][][][]
[][]</pre>
=={{header|R}}==
<syntaxhighlight lang="r">
langton.ant = function(n = 100) {
map = matrix(data = 0, nrow = n, ncol = n)
p = floor(c(n/2, n/2))
d = sample(1:4, 1)
i = 1
while(p[1] > 0 & p[1] <= n & p[2] > 0 & p[2] <= n) {
if(map[p[1], p[2]] == 1) {
map[p[1], p[2]] = 0
p = p + switch(d, c(0, 1), c(-1, 0), c(0, -1), c(1, 0))
d = ifelse(d == 4, 1, d + 1)
} else {
map[p[1], p[2]] = 1
p = p + switch(d, c(0, -1), c(1, 0), c(0, 1), c(-1, 0))
d = ifelse(d == 1, 4, d - 1)
}
}
return(map)
}
image(langton.ant(), xaxt = "n", yaxt = "n", bty = "n")
</syntaxhighlight>
=={{header|Racket}}==
[[File:Racket_Langtons_ant.png|thumb|Sample display of Racket solution]]
This Racket program attempts to avoid mutation.
<syntaxhighlight lang="racket">#lang racket
;; contracts allow us to describe expected behaviour of funcitons
(define direction/c (or/c 'u 'r 'l 'd))
(define turn/c (-> direction/c direction/c))
(define grid/c (hash/c integer? (hash/c integer? boolean?)))
(define-struct/contract ant ([d direction/c] [x integer?] [y integer?]))
(define/contract (turn-right dir) turn/c
(case dir ((u) 'r) ((d) 'l) ((r) 'd) ((l) 'u)))
(define/contract (turn-left dir) turn/c
(case dir ((u) 'l) ((d) 'r) ((r) 'u) ((l) 'd)))
(define/contract (move d x y)
(-> direction/c integer? integer? (list/c direction/c integer? integer?))
(list
d
(+ x (case d ((l) -1) ((r) 1) (else 0)))
(+ y (case d ((u) -1) ((d) 1) (else 0)))))
(define/contract (move-ant d a) (-> direction/c ant? ant?)
(apply make-ant (move d (ant-x a) (ant-y a))))
(define/contract (langton a grid) (-> ant? grid/c grid/c)
(let ((ax (ant-x a)) (ay (ant-y a)))
(if (and (<= 1 ax 100) (<= 1 ay 100))
(let* ((grid-row (hash-ref grid ay hash))
(cell-black? (hash-ref grid-row ax #f)))
(langton
(move-ant ((if cell-black? turn-left turn-right) (ant-d a)) a)
(hash-set grid ay (hash-set grid-row ax (not cell-black?)))))
grid)))
(define/contract (show-grid/text grid) (-> grid/c void?)
(for* ; for* allows us to refer to y in rw
((y (in-range 1 101))
(rw (in-value (hash-ref grid y #f)))
#:when rw ; if there is no row, the ant never visisted it
#:when (newline) ; when can be used simply for its side effect
(x (in-range 1 101)))
(case (hash-ref rw x #\?)
((#\?) (display #\space)) ; distingush between "ant-visited white" vs. pure white
((#f) (display #\:)) ; little anty footprints left
((#t) (display #\#)))))
(show-grid/text (langton (make-ant 'u 50 50) (hash)))
(require 2htdp/image)
(define/contract (show-grid/png grid) (-> grid/c image?)
(for*/fold
((scn (empty-scene 408 408)))
((y (in-range 1 101))
(rw (in-value (hash-ref grid y #f)))
#:when rw ; if there is no row, the ant never visisted it
(x (in-range 1 101)))
(case (hash-ref rw x #\?)
((#\?) scn) ; distingush between "ant-visited white" vs. pure white
((#f) (place-image (circle 2 "outline" "gray") (* x 4) (* y 4) scn)) ; little anty footprints left
((#t) (place-image (circle 2 "solid" "black") (* x 4) (* y 4) scn)))))
(show-grid/png (langton (make-ant 'u 50 50) (hash)))
</syntaxhighlight>
Output (text):
<pre style="height:60ex;overflow:scroll">
## ############ ##
#::####::::::::::# :##
###:::##::::::::::::##:#
#:#::#:::::::::#::#::::#
## ##:#:#:::::::::###:::::::#
###:#::#:::#:::::#:::::##:##::###
:#:#::###::##:####:##:::#:#::#:## ##
:#:###:##: #:##::###:#:#:::::###:::###
#:::::#:::#####:#:#::####::#:::###:#:#:#
###:##:::#:####::##:##:######:#:###:#:::#
#:###:#:##:#:#:##:##:##:#:::#####:###:##
::#:#:::#:##:###:::#:::#:#::####::::# ##
#::#:::::::::##:##:::#::##:::::##:#::: :##
###:::#:#:##:###::#::##:::::#:::###:##::##:#
#::###::##:::##:##:::###::#::::#::##:####:::#
###:::#:::#:#::#:#:####:##::#:##:###::#:::::#
#::###::#:##::::#::#:###::#::::::###:##:#::#: ##
###:::#::: #:##:#:##::##::#####:####::####:##:::#
#::###::#:# #::#:###:#:#:##::::::##:::#:#:#:: #:::#
###:::#::## ###::##:#:::##:::::::####:####:::#::::::#
#::###::#:# #:::##::###########:#::####::#::: #::::#
###:::#::## :#:####::##::#########::#::##::::#::##
#::###::#:# ## :#:##:::##:##:###:###:::#::#:##::####:#
###:::#::## #::#:######:##:#:##:#:#::::###:###:::##:::#
#::###::#:# #:::::#####:#:#####:::::#:#::##:#::::##:::#
###:::#::## #:::::#:##:#####:##::#:#:::#::#::##:# :#::#
#::###::#:# #::::#:::####:#::#####:##:::##########:::##
###:::#::## #:##:::##:::#::#:::####::#:::##:####:##:::
#::###::#:# #####:#::##:::##:#:::#::::#:#::#::#::#:#:
###:::#::## ## ## #:#:#::::##:##:#:#:##::#::##::##:
#::###::#:# #::#: #:########:#:#:##::####:#:
###:::#::## #::#: #:::::::##:##:::#::#::##:#:
#::###::#:# #::# #::::::#::##::##:::##:####:
###:::#::## ## #:::::::##::##::::#:::#:###
#::###::#:# #:##::####::::####:###:####
###:::#::## ##: ####: ##: #:##:#:#::#
#::###::#:# ## ## ## ###:##:#####
###:::#::## #:##:#::####
#::###::#:# :##:##:##
###:::#::## :##::::::
#::###::#:# #:##::####:#
###:::#::## #::#:###::###
#::###::#:# #:##:# #::#
###:::#::## ##: ##
:::##::#:# ##
##::#::##
#:#:#:#
####:##
#:##:#
####
##
</pre>
=={{header|Raku}}==
(formerly Perl 6)
{{trans|Perl}}
In this version we use 4-bits-per-char graphics to shrink the output to a quarter the area of ASCII graphics.
<syntaxhighlight lang="raku" line>constant @vecs = [1,0,1], [0,-1,1], [-1,0,1], [0,1,1];
constant @blocky = ' ▘▝▀▖▌▞▛▗▚▐▜▄▙▟█'.comb;
constant $size = 100;
enum Square <White Black>;
my @plane = [White xx $size] xx $size;
my ($x, $y) = $size/2, $size/2;
my $dir = @vecs.keys.pick;
my $moves = 0;
loop {
given @plane[$x][$y] {
when :!defined { last }
when White { $dir--; $_ = Black; }
when Black { $dir++; $_ = White; }
}
($x,$y,$moves) »+=« @vecs[$dir %= @vecs];
}
say "Out of bounds after $moves moves at ($x, $y)";
for 0,2,4 ... $size - 2 -> $y {
say join '', gather for 0,2,4 ... $size - 2 -> $x {
take @blocky[ 1 * @plane[$x][$y]
+ 2 * @plane[$x][$y+1]
+ 4 * @plane[$x+1][$y]
+ 8 * @plane[$x+1][$y+1] ];
}
}</syntaxhighlight>
{{out}}
<pre>Out of bounds after 11669 moves at (-1, 26)
▄▚▚
▟▟▜▟▚
▜▀▚▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚
▜▘▗▌▟▚ ▄
▜▘▗▌▟▘▟▘▗
▞▀▚ ▜▘▗▌▄▙▝▜
▐█ ▌▄▘▘▗▗▞▐▚▌
▌▖▝ ▐▚▙▙ ▖▀▖
▐▄▝█▀▖▄▗▗▗▀▐▛▛▙
▞▚▝▟██▜▞ ▞▗▜▌ ▞▘▌
▐▗▄▌▙▜▐▄▛▀▜▞▜▛▛▄▐
▘▗▝▜▚▖▌▟▞▛▜▌▜▖ █▌
▄▄ ▄▜▛▜▙▖▟▗▛▟▘▌ ▌
▟▖ ▘▘▄▛▌▛▟█▖ ▚▜▀ ▌
▘▘ █▚▛▜▟▌▘▗█▞▛▞▌ ▌
▐▖ ▙▐▙▗█▌▐▀ ▟▛ ▄ ▌
▟▙▚▛▀▄▗▟▖▐▗▘▛▐▀▟▌ ▌
▘▀▞▛▗▘▘█▐▞▗▗▝▟▖▄▝▝
▗▜▞▖▗▘▝█▜▞▖▗▙ ▝ ▙▌
▟▞▖▟▄▌▟▄▙▐█▗▟▙▟▚▗▞
▘▌▚▖▝▛▀ ▐▘▞█▀▟▛█▖
▄ ▝▛▚ ▀▜▙▜▜▀▜▚▄▘▙▖
▟▖▘▐▜▌▛▄▟▛▝▌ ▜▘▛▗▖▟▌
▘▀█▙▙▚▄▛▗▛▖ ▞▗▖▚▗▚▞
▜ ▖▄▙▛▚▀▗▜▛ ▞▗▝▛
▞▌▜▌█▀▀▘▖ ▙ ▌▀
▐▗▌█▛ ▀▚▞▚▞
▜▖
</pre>
=={{header|REXX}}==
This REXX program automatically justifies (or ''crops'') the '''left''', '''right''', '''top''' and '''bottom''' of the ant's walk field on
<br>the screen to display the maximum area of the ant's path (walk).
<br>Or in other words, this REXX program only shows the pertinent part of the ant's walk─field.
<syntaxhighlight lang="rexx">/*REXX program implements Langton's ant walk and displays the ant's path (finite field).*/
parse arg dir char seed . /*obtain optional arguments from the CL*/
if datatype(seed, 'W') then call random ,,seed /*Integer? Then use it as a RANDOM SEED*/
if dir=='' | dir=="," then dir= random(1, 4) /*ant is facing a random direction, */
if char=='' | char=="," then char= '#' /*binary colors: 0≡white, 1≡black. */
parse value scrSize() with sd sw . /*obtain the terminal's depth and width*/
sd= sd -6; sw= sw -1 /*adjust for " useble area. */
xHome= 1000000; yHome= 1000000 /*initially in the middle of nowhere. */
x= xHome; y= yHome /*start ant's walk in middle of nowhere*/
$.= 1 ; $.0= 4 ; $.2= 2 ; $.3= 3; $.4= 4 /* 1≡north 2≡east 3≡south 4≡west.*/
minX= x; minY= y; maxX= x; maxY= y /*initialize the min/max values for X,Y*/
@.= 0 /*the universe (walk field) is white.*/
do #=1 until (maxX-minY>sw)|(maxY-minY>sd) /*is the path out─of─bounds for screen?*/
black= @.x.y; @.x.y= \@.x.y /*invert (flip) ant's cell color code.*/
if black then dir= dir - 1 /*if cell color was black, turn left.*/
else dir= dir + 1 /* " " " " white, turn right.*/
dir= $.dir /*$ array handles/adjusts under & over.*/
select /*ant walks the direction it's facing. */
when dir==1 then y= y + 1 /*is ant walking north? Then go up. */
when dir==2 then x= x + 1 /* " " " east? " " right.*/
when dir==3 then y= y - 1 /* " " " south? " " down. */
when dir==4 then x= x - 1 /* " " " west? " " left. */
end /*select*/ /*the DIRection is always normalized.*/
minX= min(minX, x); maxX= max(maxX, x) /*find the minimum and maximum of X. */
minY= min(minY, y); maxY= max(maxY, y) /* " " " " " " Y. */
end /*steps*/ /* [↑] ant walks hither and thither. */
/*finished walking, it's out-of-bounds.*/
say center(" Langton's ant walked " # ' steps ', sw, "─")
@.xHome.yHome= '█' /*show the ant's initial starting point*/
@.x.y= '∙' /*show where the ant went out─of─bounds*/
/* [↓] show Langton's ant's trail. */
do y=maxY to minY by -1; _= /*display a single row of cells. */
do x=minX to maxX; _=_ || @.x.y /*build a cell row for the display. */
end /*x*/ /* [↓] strip trailing blanks from line*/
_= strip( translate(_, char, 10), 'T') /*color the cells: black or white. */
if _\=='' then say _ /*display line (strip trailing blanks).*/
end /*y*/ /*stick a fork in it, we're all done. */</syntaxhighlight>
Programing note: the 23<sup>rd</sup> REXX line:
<syntaxhighlight lang="rexx"> when dir==4 then x= x - 1 /* " " " west? " " left. */</syntaxhighlight>
could've been coded as:
<syntaxhighlight lang="rexx"> otherwise x= x - 1 /* " " " west? " " left. */</syntaxhighlight>
The terminal's screen size used was '''80'''<small>x</small>'''160'''.
The ant's walk starts at the █ glyph (in the middle of the "fist") and ends at <big><b>'''∙'''</b></big> (at the very top of the output) where it goes out─of─bounds.
{{out|output|text= when using the default inputs:}}
(Shown at <sup>'''1'''</sup>/<sub>'''2'''</sub> size.)
<b>
<pre style="font-size:50%">
∙
# #
## # #
### #
# ## #
## ### #
# # # ###
## # #####
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
# # ### #
## # ###
## # # ### #
## ## ## # ###
# # # ## # # # ### #
### ### # # ## # ###
# #### ## # # # ### #
## ## # ###
## ## ## # # ### #
#### # ## # ## # ###
##### ## ### ## ## ## # # ### #
# # # ## # ## #### ## ## # ###
#### ### #### #### ## # # # ### #
### # # ## ## # ## ## # ###
#### ## ## ## # # # # # # ### #
# ## # # ## ## # # # ## # ###
# #### ## # # ######## # # # # # ### #
## ## # ## # # ## ## # # # ## ## ## # ###
# # # # # # # # ## ## # ##### # # ### #
## #### ## # #### # # ## ## # ## # ###
## ########## ## ##### # #### # # # # ### #
# # # ## # # # # ## ##### ## # # ## # ###
# ## # ## # # ##### # ##### # # # ### #
# ## ### ### # # ## # ## ###### # # ## # ###
# #### ## # # ### ### #█ ## ## # ## # # ### #
## # ## # ######### ## #### # ## # ###
# # # #### # ########### ## # # # ### #
# # #### #### ## # ## ### ## # ###
# # # # # ## ## # # ### # # # # ### #
# ## #### #### ##### ## ## # ## # # ###
## # # ## ### # ### # # ## # ### #
# # ### ## # ## #### # # # # # ###
# #### ## # # ### ## ## ## ### #
# ## ## ### # ## # ### ## # # ###
## # ## ## # ## ## # #
## # #### # # # ### ## # # #
## ### ##### # ## ## ## # # ## # ### #
# # ### # ###### ## ## #### # ## ###
# # # ### # #### # # ##### # #
### ### # # ### ## # ## ### #
## ## # # # ## #### ## ### # #
### ## ## # # # # ###
# ### # # ## ##
# # # # # #
# ## ## ###
## # #### #
## ############ ##
</pre>
</b>
=={{header|Ring}}==
<syntaxhighlight lang="ring">
load "guilib.ring"
load "stdlib.ring"
new qapp
{
win1 = new qwidget() {
setwindowtitle("drawing using qpainter")
setgeometry(100,100,500,500)
label1 = new qlabel(win1) {
setgeometry(10,10,400,400)
settext("")
}
new qpushbutton(win1) {
setgeometry(200,400,100,30)
settext("draw")
setclickevent("draw()")
}
show()
}
exec()
}
func draw
p1 = new qpicture()
color = new qcolor() {
setrgb(0,0,255,255)
}
pen = new qpen() {
setcolor(color)
setwidth(1)
}
new qpainter() {
begin(p1)
setpen(pen)
fieldsize=100
field = newlist(fieldsize,fieldsize)
x=fieldsize/2
y=fieldsize/2
d=0
while x<=fieldsize and x>=0 and y<=fieldsize and y>=0
if field[x][y]=0 field[x][y]=1 d-=1 else field[x][y]=0 d+=1 ok
drawpoint(x*2, y*2)
d=(d+4) % 4
switch d
on 0 y+=1
on 1 x+=1
on 2 y-=1
on 3 x-=1
off
end
endpaint()
}
label1 { setpicture(p1) show() }
</syntaxhighlight>
Output:
[[File:CalmoSoftLangtons.jpg]]
=={{header|Ruby}}==
<syntaxhighlight lang="ruby">class Ant
class OutOfBoundsException < StandardError; end
class Plane
def initialize(x, y)
@size_x, @size_y = x, y
@cells = Array.new(y) {Array.new(x, :white)}
end
def white?(px, py)
@cells[py][px] == :white
end
def toggle_colour(px, py)
@cells[py][px] = (white?(px, py) ? :black : :white)
end
def check_bounds(px, py)
unless (0 <= px and px < @size_x) and (0 <= py and py < @size_y)
raise OutOfBoundsException, "(#@size_x, #@size_y)"
end
end
def to_s
@cells.collect {|row|
row.collect {|cell| cell == :white ? "." : "#"}.join + "\n"
}.join
end
end
dir_move = [[:north, [0,-1]], [:east, [1,0]], [:south, [0,1]], [:west, [-1,0]]]
Move = Hash[dir_move]
directions = dir_move.map{|dir, move| dir} # [:north, :east, :south, :west]
Right = Hash[ directions.zip(directions.rotate).to_a ]
Left = Right.invert
def initialize(size_x, size_y, pos_x=size_x/2, pos_y=size_y/2)
@plane = Plane.new(size_x, size_y)
@pos_x, @pos_y = pos_x, pos_y
@direction = :south
@plane.check_bounds(@pos_x, @pos_y)
end
def run
moves = 0
loop do
begin
moves += 1
move
Line 1,655 ⟶ 7,703:
moves
end
def move
@plane.
if @plane.
@direction = Right[@direction]
else
@direction = Left[@direction]
end
end
def
@pos_y += dy
@plane.check_bounds(@pos_x, @pos_y)
end
def position
"(#@pos_x, #@pos_y)"
end
def to_s
@
end
end
#
# the simulation
#
ant = Ant
moves = ant.run
puts "out of bounds after #{moves} moves: #{ant.position}"
puts ant
{{out}}
<pre style="height: 40ex; overflow: scroll">out of bounds after 11669 moves: (26, -1)
..........................#.#.......................................................................
Line 1,851 ⟶ 7,840:
....................................................................................................
....................................................................................................</pre>
'''Simple Version:'''
<syntaxhighlight lang="ruby">class Ant
MOVE = [[1,0], [0,1], [-1,0], [0,-1]] # [0]:east, [1]:south, [2]:west, [3]:north
def initialize(size_x, size_y, pos_x=size_x/2, pos_y=size_y/2)
@plane = Array.new(size_y) {Array.new(size_x, true)} # true -> white, false -> black
@sx, @sy = size_x, size_y
@px, @py = pos_x, pos_y # start position
@direction = 0 # south
@moves = 0
move while (0 <= @px and @px < @sx) and (0 <= @py and @py < @sy)
end
def move
@moves += 1
@direction = (@plane[@py][@px] ? @direction+1 : @direction-1) % 4
@plane[@py][@px] = !@plane[@py][@px]
@px += MOVE[@direction][0]
@py += MOVE[@direction][1]
end
def to_s
["out of bounds after #{@moves} moves: (#@px, #@py)"] +
(0...@sy).map {|y| (0...@sx).map {|x| @plane[y][x] ? "." : "#"}.join}
end
end
puts Ant.new(100, 100).to_s</syntaxhighlight>
;Output is the same above.
=={{header|Run BASIC}}==
<syntaxhighlight lang="runbasic">dim plane(100,100)
x = 50: y = 50: minY = 100
while (x>0) and (x<100) and (y>0) and (y<100)
if plane(x,y) then
nxt = nxt - 1
if nxt < 1 then nxt = 4
else
nxt = nxt + 1
if nxt > 4 then nxt = 1
end if
x = x + (nxt = 2) - (nxt = 4)
y = y + (nxt = 3) - (nxt = 1)
plane(x,y) = (plane(x,y) <> 1)
minY = min(y,minY) ' find lowest and
maxY = max(y,maxY) ' highest y to prevent printing blank lines
wend
graphic #g, 100,100
for y = minY to maxY
for x = 1 to 100
print chr$((plane(x,y)*3) + 32);
if plane(x,y) = 1 then #g "color green ; set "; x; " "; y else #g "color blue ; set "; x; " "; y
next x
print y
next y
render #g
#g "flush""</syntaxhighlight>
Ouptut (Produces both character and graphic):[[File:Langtons_ant_run_basic.png|right|graphic]]
<pre style="height: 40ex; overflow: scroll"> 20
## 21
## 22
## ## ### ## # 23
# ## ### #### # # 24
# ## # ## ## # # 25
## # # ####### ### ## 26
# # # ## # # ##### # # 27
### # #### ## ### # ## 28
## # # ## # # ## #### ###### 29
# # # # ## ## # # ##### # 30
### ## # # # ##### # ## # ### 31
## ## ### ## ### ## #### # # 32
### ### # # # ### # # ## 33
# # ######### ##### #### 34
### ### ## # # # ## # 35
##### ##### ## ##### # # # 36
## # ####### ### ###### ##### # ### 37
# ## ## ### # # # # # # 38
### ### # ## ## # # ## # 39
# # # # # ##### # # ## 40
## ### # # ## ## # # # 41
# # # # # # ## # # ### ## # 42
# ### # # # # #### ## ## #### 43
# ## ### ## # # # #### # ## 44
# ## ### # #### ### ## ## 45
# ### ### ### ## # # 46
# # # # #### #### ## ## 47
# ## ### ## # ## #### ### # # 48
# # # ##### # # ### ### 49
# #### # ### ## ### # # # 50
# # ## ## ## #### ## ## #### 51
# # ## ## # ####### 52
### ## ## # ### # ## # # 53
### ## ###### # # #### # 54
# ## # ## ## #### # ## #### # 55
# ####### ###### # ## # # # 56
# # ## # # ## ###### # # 57
# ## ### # # ####### # ## 58
## # ## # # # ## # ## ### 59
###### ## ##### # 60
# # ##### # # # 61
## # # ## # # 62
## # ## # ## # ### 63
# ## # # # # ### 64
# #### ## # # # 65
### # # ### #### 66
# ## ## ## # 67
## ## # ### 68
## # ## ## # 69
## # ### 70
# ## ## # 71
## # ### 72
# ## ## # 73
## # ### 74
# ## ## # 75
## # ### 76
# ## ## # 77
## # ### 78
# ## ## # 79
## # ### 80
# ## ## # 81
## # ### 82
# ## ## # 83
## # ### 84
# ## ## # 85
## # ### 86
# ## ## # 87
## # ### 88
# ## ## # 89
## # ### 90
# ## ## # 91
## # ### 92
# ## ## # 93
## # ### 94
# ## ## # 95
## # ##### 96
# # #### 97
## ### # 98
# # ## 99
100
</pre>
=={{header|Rust}}==
<syntaxhighlight lang="rust">struct Ant {
x: usize,
y: usize,
dir: Direction
}
#[derive(Clone,Copy)]
enum Direction {
North,
East,
South,
West
}
use Direction::*;
impl Ant {
fn mv(&mut self, vec: &mut Vec<Vec<u8>>) {
let pointer = &mut vec[self.y][self.x];
//change direction
match *pointer {
0 => self.dir = self.dir.right(),
1 => self.dir = self.dir.left(),
_ => panic!("Unexpected colour in grid")
}
//flip colour
//if it's 1 it's black
//if it's 0 it's white
*pointer ^= 1;
//move direction
match self.dir {
North => self.y -= 1,
South => self.y += 1,
East => self.x += 1,
West => self.x -= 1,
}
}
}
impl Direction {
fn right(self) -> Direction {
match self {
North => East,
East => South,
South => West,
West => North,
}
}
fn left(self) -> Direction {
//3 rights equal a left
self.right().right().right()
}
}
fn main(){
//create a 100x100 grid using vectors
let mut grid: Vec<Vec<u8>> = vec![vec![0; 100]; 100];
let mut ant = Ant {
x: 50, y: 50, dir: Direction::North
};
while ant.x < 100 && ant.y < 100 {
ant.mv(&mut grid);
}
for each in grid.iter() {
//construct string
//using iterator methods to quickly convert the vector
//to a string
let string = each.iter()
.map(|&x| if x == 0 { " " } else { "#" })
.fold(String::new(), |x, y| x+y);
println!("{}", string);
}
}</syntaxhighlight>
=={{header|Scala}}==
<syntaxhighlight lang="scala">class Langton(matrix:Array[Array[Char]], ant:Ant) {
import Langton._
val rows=matrix.size
val cols=matrix(0).size
def isValid = 0 <= ant.row && ant.row < cols && 0 <= ant.col && ant.col < rows
def isBlack=matrix(ant.row)(ant.col)==BLACK
def changeColor(c:Char)={matrix(ant.row)(ant.col)=c; matrix}
def evolve():Langton={
val (newCol, newAnt)=if(isBlack) (WHITE, ant.turnLeft) else (BLACK, ant.turnRight)
new Langton(changeColor(newCol), newAnt.move)
}
override def toString()=matrix map (_.mkString("")) mkString "\n"
}
case class Ant(row:Int, col:Int, d:Int=0) {
def turnLeft=Ant(row,col,(d-1)&3)
def turnRight=Ant(row,col,(d+1)&3)
def move=d match {
case 0 => Ant(row-1,col,d) // north
case 1 => Ant(row,col+1,d) // east
case 2 => Ant(row+1,col,d) // south
case 3 => Ant(row,col-1,d) // west
}
}
object Langton {
val BLACK='#'
val WHITE='.'
def apply(x:Int=100, y:Int=100)=new Langton(Array.fill(y, x)(WHITE), Ant(x>>>1, y>>>1, 0))
def main(args: Array[String]): Unit = {
var l=Langton(100,100)
var moves=0
while (l.isValid) {
moves += 1
l=l.evolve
}
println("Out of bounds after "+moves+" moves")
println(l)
}
}</syntaxhighlight>
Output:
<pre style="height: 40ex; overflow: scroll">Out of bounds after 11669 moves
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..................#..###..#.#.....#....#...####.#..#####.##...##########...##.......................
.................###...#..##......#.##...##...#..#...####..#...##.####.##...........................
................#..###..#.#........#####.#..##...##.#...#....#.#..#..#..#.#.........................
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=={{header|Scilab}}==
{{works with|Scilab|5.4.1 or above}}
<syntaxhighlight lang="text">grid_size=100; //side length of the square grid
ant_pos=round([grid_size/2 grid_size/2]); //ant's initial position at center of grid
head_direction='W'; //ant's initial direction can be either
//'N' north, 'S' south, 'E' east, or 'W' west
grid=~zeros(grid_size,grid_size) //blank grid
col=[]; //cell color handler
next_step=%T; //step flag
i=0; //step counter
while next_step
col=grid(ant_pos(1),ant_pos(2)); //get cell color
if col then //if white cell
grid(ant_pos(1),ant_pos(2))=~grid(ant_pos(1),ant_pos(2)); //switch color
if head_direction=='N' then //if head to N
head_direction='E'; //turn right to E
ant_pos(2)=ant_pos(2)+1; //step forward
elseif head_direction=='E' then //if head to E
head_direction='S'; //turn right to S
ant_pos(1)=ant_pos(1)+1; //step forward
elseif head_direction=='S' then //if head to S
head_direction='W'; //turn right to W
ant_pos(2)=ant_pos(2)-1; //step forward
elseif head_direction=='W' then //if head to W
head_direction='N'; //turn right to N
ant_pos(1)=ant_pos(1)-1; //step forward
end
else //if black cell
grid(ant_pos(1),ant_pos(2))=~grid(ant_pos(1),ant_pos(2)); //switch color
if head_direction=='N' then //if head to N
head_direction='W'; //turn left to E
ant_pos(2)=ant_pos(2)-1; //step foward
elseif head_direction=='W' then //if head to W
head_direction='S'; //turn left to S
ant_pos(1)=ant_pos(1)+1; //step forward
elseif head_direction=='S' then //if head to S
head_direction='E'; //turn left to E
ant_pos(2)=ant_pos(2)+1; //step forward
elseif head_direction=='E' then //if head to E
head_direction='N'; //turn left to N
ant_pos(1)=ant_pos(1)-1; //step forward
end
end
i=i+1;
if ant_pos(1)<1 | ant_pos(1)>100 | ant_pos(2)<0 | ant_pos(2)>100 then //check ant's position
disp("Out of bounds after "+string(i)+" steps");
next_step=~next_step; //break loop if out of bounds
end
end
ascii_grid=string(zeros(grid)); //create grid of chars to display
//on the console
for a=1:length(grid)
if grid(a) then
ascii_grid(a)=" "; //blank space if cell is white
else
ascii_grid(a)="#"; //# if cell is black
end
end
disp(ascii_grid);</syntaxhighlight>
{{out}}
<pre style="font-size: 10px">
Out of bounds after 11669 steps
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=={{header|Seed7}}==
<syntaxhighlight lang="seed7">$ include "seed7_05.s7i";
const type: direction is new enum UP, RIGHT, DOWN, LEFT end enum;
const proc: main is func
local
const integer: width is 75;
const integer: height is 52;
var array array boolean: m is height times width times FALSE;
var direction: dir is UP;
var integer: x is width div 2;
var integer: y is height div 2;
begin
while x in {1 .. width} and y in {1 .. height} do
dir := direction conv ((ord(dir) + 2 * ord(m[y][x]) - 1) mod 4);
m[y][x] := not m[y][x];
case dir of
when {UP}: decr(y);
when {RIGHT}: decr(x);
when {DOWN}: incr(y);
when {LEFT}: incr(x);
end case;
end while;
for key x range m do
for y range 1 to width do
write(".#"[succ(ord(m[x][y]))]);
end for;
writeln;
end for;
end func;</syntaxhighlight>
{{out}}
<pre>
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...................###.#..#...#.....#.....##.##..###.......................
....................#.#..###..##.####.##...#.#..#.##..##...................
....................#.###.##..#.##..###.#.#.....###...###..................
..................#.....#...#####.#.#..####..#...###.#.#.#.................
.................###.##...#.####..##.##.######.#.###.#...#.................
.................#.###.#.##.#.#.##.##.##.#...#####.###.##..................
.....................#.#...#.##.###...#...#.#..####....#.##................
..................#..#.........##.##...#..##.....##.#.....##...............
.................###...#.#.##.###..#..##.....#...###.##..##.#..............
................#..###..##...##.##...###..#....#..##.####...#..............
...............###...#...#.#..#.#.####.##..#.##.###..#.....#...............
..............#..###..#.##....#..#.###..#......###.##.#..#..##.............
.............###...#.....#.##.#.##..##..#####.####..####.##...#............
............#..###..#.#.#..#.###.#.#.##......##...#.#.#....#...#...........
...........###...#..##.###..##.#...##.......####.####...#......#...........
..........#..###..#.#..#...##..###########.#..####..#....#....#............
.........###...#..##......#.####..##..#########..#..##....#..##............
........#..###..#.#...##..#.##...##.##.###.###...#..#.##..####.#...........
.......###...#..##...#..#.######.##.#.##.#.#....###.###...##...#...........
......#..###..#.#...#.....#####.#.#####.....#.#..##.#....##...#............
.....###...#..##....#.....#.##.#####.##..#.#...#..#..##.#..#..#............
....#..###..#.#.....#....#...####.#..#####.##...##########...##............
...###...#..##......#.##...##...#..#...####..#...##.####.##................
..#..###..#.#........#####.#..##...##.#...#....#.#..#..#..#.#..............
.###...#..##..........##..##.#.#.#....##.##.#.#.##..#..##..##..............
#..###..#.#.................#..#....#.########.#.#.##..####.#..............
.###.#..##..................#..#...#.......##.##...#..#..##.#..............
#.#.#.#.#....................#..#..#......#..##..##...##.####..............
.####.##......................##...#.......##..##....#...#.###.............
.#.##.#............................#.##..####....####.###.####.............
..####..............................##..####....##..#.##.#.#..#............
...##................................##....##....##.###.##.#####...........
....................................................#.##.#..####...........
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</pre>
=={{header|Sidef}}==
{{trans|Raku}}
<syntaxhighlight lang="ruby">define dirs = [[1,0], [0,-1], [-1,0], [0,1]]
define size = 100
enum |White, Black|
var plane = size.of { size.of (White) }
var (x, y) = ([size >> 1] * 2)...
var dir = dirs.len.irand
var moves = 0
loop {
(x >= 0) && (y >= 0) && (x < size) && (y < size) || break
given (plane[x][y]) {
when (White) { dir--; plane[x][y] = Black }
when (Black) { dir++; plane[x][y] = White }
}
++moves
[[\x, \y], dirs[dir %= dirs.len]].zip {|a,b| *a += b }
}
say "Out of bounds after #{moves} moves at (#{x}, #{y})"
plane.map{.map {|square| square == Black ? '#' : '.' }}.each{.join.say}</syntaxhighlight>
=={{header|Swift}}==
{{trans|C#}}
<syntaxhighlight lang="swift">import Foundation
let WIDTH = 100
let HEIGHT = 100
struct Point {
var x:Int
var y:Int
}
enum Direction: Int {
case North = 0, East, West, South
}
class Langton {
let leftTurn = [Direction.West, Direction.North, Direction.South, Direction.East]
let rightTurn = [Direction.East, Direction.South, Direction.North, Direction.West]
let xInc = [0, 1,-1, 0]
let yInc = [-1, 0, 0, 1]
var isBlack:[[Bool]]
var origin:Point
var antPosition = Point(x:0, y:0)
var outOfBounds = false
var antDirection = Direction.East
init(width:Int, height:Int) {
self.origin = Point(x:width / 2, y:height / 2)
self.isBlack = Array(count: width, repeatedValue: Array(count: height, repeatedValue: false))
}
func moveAnt() {
self.antPosition.x += xInc[self.antDirection.rawValue]
self.antPosition.y += yInc[self.antDirection.rawValue]
}
func step() -> Point {
if self.outOfBounds {
println("Ant tried to move while out of bounds.")
exit(0)
}
var ptCur = Point(x:self.antPosition.x + self.origin.x, y:self.antPosition.y + self.origin.y)
let black = self.isBlack[ptCur.x][ptCur.y]
let direction = self.antDirection.rawValue
self.antDirection = (black ? self.leftTurn : self.rightTurn)[direction]
self.isBlack[ptCur.x][ptCur.y] = !self.isBlack[ptCur.x][ptCur.y]
self.moveAnt()
ptCur = Point(x:self.antPosition.x + self.origin.x, y:self.antPosition.y + self.origin.y)
self.outOfBounds =
ptCur.x < 0 ||
ptCur.x >= self.isBlack.count ||
ptCur.y < 0 ||
ptCur.y >= self.isBlack[0].count
return self.antPosition
}
}
let ant = Langton(width: WIDTH, height: HEIGHT)
while !ant.outOfBounds {
ant.step()
}
for row in 0 ..< WIDTH {
for col in 0 ..< HEIGHT {
print(ant.isBlack[col][row] ? "#" : " ")
}
println()
}</syntaxhighlight>
{{out}}
Blank lines omitted
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=={{header|Tcl}}==
{{libheader|Tk}}
[[File:LangtonAnt_Tcl.gif|thumb|Output of Tcl solution of Langton's ant task]]
<
proc step {workarea} {
Line 1,887 ⟶ 8,798:
# Produce output in file
antgrid write ant.gif -format gif</
=={{header|TI-83 BASIC}}==
The
<
:ClrDraw
:0→N
:47→A
:31→B
:90→Θ
:Repeat getKey
:If pxl-Test(
:Then
:Θ+90→Θ
Line 1,905 ⟶ 8,815:
:Θ-90→Θ
:End
:Pxl-Change(
:
:
:N+1→N
:End
</syntaxhighlight>
=={{header|UNIX Shell}}==
{{works with|Bourne Again SHell}}
{{works with|Korn Shell}}
{{works with|Z Shell}}
This uses the terminal dimensions, so shrink the font and make the window big; should be at least 80 lines by 100 columns.
<syntaxhighlight lang="sh">function main {
typeset -i width=$(tput cols)
typeset -i height=$(tput lines)
typeset -a grid
typeset -i i
for (( i=0; i<height; ++i )); do
grid+=("$(printf "%${width}s" ' ')")
done
typeset -i x=$(( width / 2 )) y=$(( height / 2 ))
(( dx=0, dy = 1 - 2*RANDOM%2 ))
if (( RANDOM % 2 )); then
(( dy=0, dx = 1 - 2*RANDOM%2 ))
fi
printf '\e[H';
printf '%s\n' "${grid[@]}"
tput civis
while (( x>=0 && x < width && y >=0 && y< height)); do
(( i=y ))
if [[ -n $ZSH_VERSION ]]; then
(( i += 1 ))
fi
ch=${grid[i]:$x:1}
if [[ $ch == '#' ]]; then
(( t=dx, dx=dy, dy=-t ))
grid[i]=${grid[i]:0:$x}' '${grid[i]:$x+1}
else
(( t=dx, dx=-dy, dy=t ))
grid[i]=${grid[i]:0:$x}'#'${grid[i]:$x+1}
fi
(( x += dx, y += dy ))
tput cup $y 0 && printf '%s' "${grid[i]}"
done
tput cnorm
read line
return
}
main "$@"</syntaxhighlight>
{{Out}}
Example final state:
<pre> ## # #
### # #
# ## ##
## ## #
# # # ##
## # ### #
# # ### ##
## # ####
# # ### ##
## # ####
# # ### ##
## # ####
# # ### ##
## # ####
# # ### ##
## # ####
# # ### ##
## # ####
## # # ### ##
## ## ## # ####
# # # ## # # # ### ##
### ### # # ## # ####
# #### ## # # # ### ##
## ## # ####
## ## ## # # ### ##
#### # ## # ## # ####
##### ## ### ## ## ## # # ### ##
# # # ## # ## #### ## ## # ####
#### ### #### #### ## # # # ### ##
### # # ## ## # ## ## # ####
#### ## ## ## # # # # # # ### ##
# ## # # ## ## # # # ## # ####
# #### ## # # ######## # # # # # ### ##
## ## # ## # # ## ## # # # ## ## ## # ####
# # # # # # # # ## ## # ##### # # ### ##
## #### ## # #### # # ## ## # ## # ####
## ########## ## ##### # #### # # # # ### ##
# # # ## # # # # ## ##### ## # # ## # ####
# ## # ## # # ##### # ##### # # # ### ##
# ## ### ### # # ## # ## ###### # # ## # ####
# #### ## # # ### ### ## ## ## # ## # # ### ##
## # ## # ######### ## #### # ## # ####
# # # #### # ########### ## # # # ### ##
# # #### #### ## # ## ### ## # ####
# # # # # ## ## # # ### # # # # ### ##
# ## #### #### ##### ## ## # ## # # ####
## # # ## ### # ### # # ## # ### ##
# # ### ## # ## #### # # # # # ####
# #### ## # # ### ## ## ## ### ##
# ## ## ### # ## # ### ## # # ####
## # ## ## # ## ## # ##
## # #### # # # ### ## # ###
## ### ##### # ## ## ## # # ## ### #
# # ### # ###### ## ## #### # # ###
# # # ### # #### # # ##### # # #
### ### # # ### ## # ## ###
## ## # # # ## #### ## ### # ##
### ## ## # # # # # #
# ### # # ## #
# # # # #
# ## ## # #
## # #### ##
## ############ #
</pre>
=={{header|VBA}}==
<syntaxhighlight lang="vb">
Option Explicit
Sub Ant()
Dim TablDatas(1 To 200, 1 To 256) As String, sDir As String, sFile As String, Str As String
Dim ColA As Integer, LigA As Long, ColF As Integer, LigF As Long, i As Long, j As Integer, Num As Long
Dim Top As Boolean, Left As Boolean, Bottom As Boolean, Right As Boolean
'init variables
Select Case Int(Rnd(4) * 4)
Case 0: Top = True
Case 1: Right = True
Case 2: Bottom = True
Case 3: Left = True
End Select
LigF = 80
ColF = 50
For i = 1 To 200
For j = 1 To 256
TablDatas(i, j) = " "
Next
Next
'directory
sDir = "/Users/mjreed/Desktop/"
'name txt file
sFile = "Langton_Ant.txt"
'start
Dim Dir As String
For i = 1 To 15000
LigA = LigF
ColA = ColF
If LigA = 1 Or ColA = 1 Or ColA = 256 Or LigA = 200 Then GoTo Fin
If TablDatas(LigA, ColA) = " " Then
TablDatas(LigA, ColA) = "#"
Select Case True
Case Top: Top = False: Right = True: LigF = LigA: ColF = ColA + 1
Case Left: Left = False: Top = True: LigF = LigA - 1: ColF = ColA
Case Bottom: Bottom = False: Left = True: LigF = LigA: ColF = ColA - 1
Case Right: Right = False: Bottom = True: LigF = LigA + 1: ColF = ColA
End Select
Else
TablDatas(LigA, ColA) = " "
Select Case True
Case Top: Top = False: Left = True: LigF = LigA: ColF = ColA - 1
Case Left: Left = False: Bottom = True: LigF = LigA + 1: ColF = ColA
Case Bottom: Bottom = False: Right = True: LigF = LigA: ColF = ColA + 1
Case Right: Right = False: Top = True: LigF = LigA - 1: ColF = ColA
End Select
End If
Next i
Fin:
'result in txt file
Num = FreeFile
Open sDir & sFile For Output As #Num
For i = 1 To UBound(TablDatas, 1)
Str = vbNullString
For j = 1 To UBound(TablDatas, 2)
Str = Str & TablDatas(i, j)
Next j
Print #Num, Str
Next i
Close #Num
Exit Sub
End Sub
</syntaxhighlight>
{{out}}
Blank lines elided
<pre> ## ##
######
## ## #
# # ##
#### ### #
##### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## #
### # ##
# ## ## # ##
### # ## ##
# ## ## ## #
#### ### # # ###
# # # ## #### #
### # # # # ## #
### # ## # ## # ##
# # ## # # ##
# # # ##### # #
# ##### ## ######
### ## # ## # # # ## # ##
## # ####### # # ### ## #
# # ###### ## # # ## # #
# # # ## # ###### ####### #
# #### ## # #### ## ## # ## #
# #### # # ###### ## ###
# # ## # ### # ## ## ###
####### # ## ## # #
#### ## ## #### ## ## ## # #
# # # ### ## ### # #### #
### ### # # ##### # # #
# # ### #### ## # ## ### ## #
## ## #### #### # # # #
# # ## ### ### ### #
## ## ### #### # ### ## #
## # #### # # # ## ### ## #
#### ## ## #### # # # # ### #
# ## ### # # ## # # # # # #
# # # ## ## # # ### ##
## # # ##### # # # # #
# ## # # ## ## # ### ###
# # # # # # ### ## ## #
### # ##### ###### ### ####### # ##
# # # ##### ## ##### #####
# ## # # # ## ### ###
#### ##### ######### # #
## # # ### # # # ### ###
# # #### ## ### ## ### ## ##
### # ## # ##### # # # ## ###
# ##### # # ## ## # # # #
###### #### ## # # ## # # ##
## # ### ## #### # ###
# # ##### # # ## # # #
## ### ####### # # ##
# # ## ## # ## #
# # #### ### ## #
# ## ### ## ##
##
##
</pre>
=={{header|Vim Script}}==
<syntaxhighlight lang="vim">" return character under cursor
function! CurrChar()
return matchstr(getline('.'), '\%' . col('.') . 'c.')
endfunction
" draw all-white grid (arguments are characters to use for white and black)
function! LangtonClear(white, black)
let l:bufname = 'langtons.ant'
if bufexists(l:bufname)
let l:winnum = bufwinnr(l:bufname)
if l:winnum == -1
execute 'sbuffer ' . bufnr(l:bufname)
else
execute l:winnum . 'wincmd w'
endif
else
execute 'new ' . l:bufname
end
execute '1,$ delete _'
call append(0, repeat(a:white,100))
execute 'normal! 1Gyy99p'
goto 5100
let b:directions = [ 'k', 'l', 'j', 'h' ]
let b:direction = 0
let b:white = a:white
let b:black = a:black
endfunction
" move the ant one step
function! LangtonStep()
let l:ch = CurrChar()
if l:ch == b:white
let l:ch = b:black
let b:direction = (b:direction + 1) % 4
elseif l:ch == b:black
let l:ch = b:white
let b:direction = (b:direction + 3) % 4
endif
execute 'normal! r'.l:ch.b:directions[b:direction]
endfunction
" run until we hit the edge
" optional arguments specify white and black characters;
" default . and @, respectively.
function! RunLangton(...)
let l:white='.'
let l:black='@'
if a:0 > 0
let l:white=a:1
if a:0 > 1
let l:black=a:2
endif
endif
call LangtonClear(l:white, l:black)
while 1
let l:before = getpos('.')
call LangtonStep()
let l:after = getpos('.')
if l:before == l:after
break
endif
endwhile
endfunction</syntaxhighlight>
=={{header|Whitespace}}==
<syntaxhighlight lang="whitespace">
</syntaxhighlight>
Following is the pseudo-Assembly from which the above was generated.
<syntaxhighlight lang="asm">; For easier access, the direction vector is stored at the end of the heap.
push 10003 dup push 100 store
push 1 sub dup push -1 store
push 1 sub dup push -100 store
push 1 sub dup push 1 store
0: ; Initialize the grid.
push 1 sub dup push 0 store
dup push 0 swap sub jn 0
push 5050 ; Start the ant at the center.
1: ; Make sure the ant's in bounds.
dup push 100 mod jn 2
dup push 100 div jn 2
push 100 copy 1 copy 1 mod sub jz 2
push 100 copy 1 copy 1 div sub jz 2
swap copy 1 load ; Get current cell state.
push 1 add push 2 mod ; Invert it.
copy 2 copy 1 store ; Then store it back.
push 2 mul push 5 add add push 4 mod ; Determine new direction.
swap copy 1 push 10000 add load add ; Update position accordingly.
jump 1
2: ; Initialize a counter and flow into the printer.
pop dup sub
3: ; Iterate over the cells.
dup load push 32 add ochr ; Print ' ' for off, '!' for on.
push 1 add dup ; Increment the counter.
push 100 mod jz 5 ; Branch at the end of a row.
4:
dup push 10000 sub jn 3 ; Go again unless counter is 10000.
pop exit ; All done, exit clean.
5: ; Print a newline and jump back to the counter check.
push 10 ochr jump 4</syntaxhighlight>
=={{header|Wren}}==
{{trans|D}}
The textual version only.
<syntaxhighlight lang="wren">var width = 75
var height = 52
var maxSteps = 12000
var up = 0
var right = 1
var down = 2
var left = 3
var direction = [up, right, down, left]
var white = 0
var black = 1
var x = (width/2).floor
var y = (height/2).floor
var m = List.filled(height, null)
for (i in 0...height) m[i] = List.filled(width, 0)
var dir = up
var i = 0
while (i < maxSteps && 0 <= x && x < width && 0 <= y && y < height) {
var turn = (m[y][x] == black)
var index = (dir + (turn ? 1 : -1)) & 3
dir = direction[index]
m[y][x] = (m[y][x] == black) ? white : black
if (dir == up) {
y = y - 1
} else if (dir == right) {
x = x - 1
} else if (dir == down) {
y = y + 1
} else {
x = x + 1
}
i = i + 1
}
for (j in 0...height) {
for (k in 0...width) System.write((m[j][k] == white) ? "." : "#")
System.print()
}</syntaxhighlight>
{{out}}
<pre>
Same as D entry.
</pre>
=={{header|XPL0}}==
[[File:AntXPL0.gif|right]]
<syntaxhighlight lang="xpl0">include c:\cxpl\codes; \intrinsic 'code' declarations
int X, Y, Dir;
[SetVid($13); \set 320x200 graphic video mode
X:= 50; Y:= 50; Dir:= 0; \start in middle facing east
repeat if ReadPix(X,Y) then \(black and white are reversed)
[Dir:= Dir-1;\left\ Point(X,Y, 0\black\)]
else [Dir:= Dir+1;\right\ Point(X,Y,$F\white\)];
case Dir & 3 of
0: X:= X+1; \east
1: Y:= Y+1; \south
2: X:= X-1; \west
3: Y:= Y-1 \north
other [];
until X<0 ! X>=100 ! Y<0 ! Y>=100;
X:= ChIn(1); \wait for keystroke
SetVid(3); \restore normal text mode
]</syntaxhighlight>
=={{header|zkl}}==
[[File:AntXPL0.gif|right]]
{{trans|XPL0}}
Uses the PPM class from http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm#zkl
<syntaxhighlight lang="zkl">white:=0xff|ff|ff; black:=0;
w:=h:=100; bitmap:=PPM(w,h,white);
x:=w/2; y:=h/2; dir:=0; // start in middle facing east
do{
if(bitmap[x,y]){ dir-=1; bitmap[x,y]=black; } // white-->black, turn left
else { dir+=1; bitmap[x,y]=white; } // black-->white, turn right
switch(dir.bitAnd(3)){ // dir is always <0
case(0){ x+=1; } // east
case(1){ y-=1; } // south
case(2){ x-=1; } // west
case(3){ y+=1; } // north
}
}while((0<=x<w) and (0<=y<h));
bitmap.write(File("foo.ppm","wb"));</syntaxhighlight>
{{out}}
Same as XPL0 (and using their image).
| |||