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# One-dimensional cellular automata

One-dimensional cellular automata
You are encouraged to solve this task according to the task description, using any language you may know.

Assume an array of cells with an initial distribution of live and dead cells, and imaginary cells off the end of the array having fixed values.

Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current generation.

If, in the following table, a live cell is represented by 1 and a dead cell by 0 then to generate the value of the cell at a particular index in the array of cellular values you use the following table:

```000 -> 0  #
001 -> 0  #
010 -> 0  # Dies without enough neighbours
011 -> 1  # Needs one neighbour to survive
100 -> 0  #
101 -> 1  # Two neighbours giving birth
110 -> 1  # Needs one neighbour to survive
111 -> 0  # Starved to death.
```

## 11l

Translation of: Python
`V gen = ‘_###_##_#_#_#_#__#__’.map(ch -> Int(ch == ‘#’))L(n) 10   print(gen.map(cell -> (I cell != 0 {‘#’} E ‘_’)).join(‘’))   gen = [0] [+] gen [+] [0]   gen = (0 .< gen.len - 2).map(m -> Int(sum(:gen[m .+ 3]) == 2))`
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
```

## 8th

` \ one-dimensional automaton \ direct map of input state to output state:{  "   " : 32,  "  #" : 32,  " # " : 32,  " ##" : 35,  "#  " : 32,  "# #" : 35,  "## " : 35,  "###" : 32,} var, lifemap : transition \ s ix (r:s') -- (r:s')    >r dup [email protected] n:1- 3 s:slice    lifemap @ swap caseof    r> swap [email protected] -rot s:! >r ; \ run over 'state' and generate new state: gen \ s -- s'  clone >r  dup s:len 2 n:-  ' transition 1 rot loop  drop r> ; : life \ s -- s'  dup . cr gen  ; " ### ## # # # #  #  " ' life 10 timesbye  `

## ACL2

`(defun rc-step-r (cells)   (if (endp (rest cells))       nil       (cons (if (second cells)                 (xor (first cells) (third cells))                 (and (first cells) (third cells)))             (rc-step-r (rest cells))))) (defun rc-step (cells)   (cons (and (first cells) (second cells))         (rc-step-r cells))) (defun rc-steps-r (cells n prev)   (declare (xargs :measure (nfix n)))   (if (or (zp n) (equal cells prev))       nil       (let ((new (rc-step cells)))          (cons new (rc-steps-r new (1- n) cells))))) (defun rc-steps (cells n)  (cons cells (rc-steps-r cells n nil))) (defun pretty-row (row)   (if (endp row)       (cw "~%")       (prog2\$ (cw (if (first row) "#" "-"))               (pretty-row (rest row))))) (defun pretty-output (out)   (if (endp out)       nil       (prog2\$ (pretty-row (first out))               (pretty-output (rest out)))))`

## Action!

`CHAR FUNC CalcCell(CHAR prev,curr,next)  IF prev='. AND curr='# AND next='# THEN    RETURN ('#)  ELSEIF prev='# AND curr='. AND next='# THEN    RETURN ('#)  ELSEIF prev='# AND curr='# AND next='. THEN    RETURN ('#)  FIRETURN ('.) PROC NextGeneration(CHAR ARRAY s)  BYTE i  CHAR prev,curr,next   IF s(0)<4 THEN RETURN FI  prev=s(1) curr=s(2) next=s(3)  i=2  DO    s(i)=CalcCell(prev,curr,next)    i==+1    IF i=s(0) THEN EXIT FI    prev=curr curr=next next=s(i+1)  ODRETURN PROC Main()  DEFINE MAXGEN="9"  CHAR ARRAY s=".###.##.#.#.#.#..#.."  BYTE i   FOR i=0 TO MAXGEN  DO    PrintF("Generation %I: %S%E",i,s)    IF i<MAXGEN THEN      NextGeneration(s)    FI  ODRETURN`
Output:
```Generation 0: .###.##.#.#.#.#..#..
Generation 1: .#.#####.#.#.#......
Generation 2: ..##...##.#.#.......
Generation 3: ..##...###.#........
Generation 4: ..##...#.##.........
Generation 5: ..##....###.........
Generation 6: ..##....#.#.........
Generation 7: ..##.....#..........
Generation 8: ..##................
Generation 9: ..##................
```

`with Ada.Text_IO;  use Ada.Text_IO; procedure Cellular_Automata is   type Petri_Dish is array (Positive range <>) of Boolean;    procedure Step (Culture : in out Petri_Dish) is      Left  : Boolean := False;      This  : Boolean;      Right : Boolean;   begin      for Index in Culture'First..Culture'Last - 1 loop         Right := Culture (Index + 1);         This  := Culture (Index);         Culture (Index) := (This and (Left xor Right)) or (not This and Left and Right);         Left := This;      end loop;      Culture (Culture'Last) := Culture (Culture'Last) and not Left;   end Step;    procedure Put (Culture : Petri_Dish) is   begin      for Index in Culture'Range loop         if Culture (Index) then            Put ('#');         else            Put ('_');         end if;      end loop;   end Put;    Culture : Petri_Dish :=      (  False, True, True,  True, False, True,  True, False, True, False, True,         False, True, False, True, False, False, True, False, False      );begin   for Generation in 0..9 loop      Put ("Generation" & Integer'Image (Generation) & ' ');      Put (Culture);      New_Line;      Step (Culture);   end loop;end Cellular_Automata;`

The implementation defines Petri dish type with Boolean items identifying whether a place is occupied by a living cell. State transition is determined by a simple Boolean expression of three arguments.

Output:
```Generation 0 _###_##_#_#_#_#__#__
Generation 1 _#_#####_#_#_#______
Generation 2 __##___##_#_#_______
Generation 3 __##___###_#________
Generation 4 __##___#_##_________
Generation 5 __##____###_________
Generation 6 __##____#_#_________
Generation 7 __##_____#__________
Generation 8 __##________________
Generation 9 __##________________
```

## ALGOL 68

### Using the low level packed arrays of BITS manipulation operators

Works with: ALGOL 68 version Revision 1 - no extensions to language used
Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny
`INT stop generation = 9;INT universe width = 20;FORMAT alive or dead = \$b("#","_")\$; BITS universe := 2r01110110101010100100;   # universe := BIN ( ENTIER ( random * max int ) ); #INT upb universe = bits width;INT lwb universe = bits width - universe width + 1; PROC couple = (BITS parent, INT lwb, upb)BOOL: (  SHORT INT sum := 0;  FOR bit FROM lwb TO upb DO    sum +:= ABS (bit ELEM parent)  OD;  sum = 2); FOR generation FROM 0 WHILE  printf((\$"Generation "d": "\$, generation,         \$f(alive or dead)\$, []BOOL(universe)[lwb universe:upb universe],         \$l\$));# WHILE # generation < stop generation DO  BITS next universe := 2r0;     # process the first event horizon manually #  IF couple(universe,lwb universe,lwb universe + 1) THEN     next universe := 2r10  FI;   # process the middle kingdom in a loop #  FOR bit FROM lwb universe + 1 TO upb universe - 1 DO     IF couple(universe,bit-1,bit+1) THEN      next universe := next universe OR 2r1    FI;    next universe := next universe SHL 1  OD;    # process the last event horizon manually #  IF couple(universe, upb universe - 1, upb universe) THEN     next universe := next universe OR 2r1  FI;  universe := next universeOD`
Output:
```Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________
```

### Using high level BOOL arrays

Works with: ALGOL 68 version Revision 1 - no extensions to language used
Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny
`INT stop generation = 9;INT upb universe = 20;FORMAT alive or dead = \$b("#","_")\$; BITS bits universe := 2r01110110101010100100;   # bits universe := BIN ( ENTIER ( random * max int ) ); #[upb universe] BOOL universe := []BOOL(bits universe)[bits width - upb universe + 1:]; PROC couple = (REF[]BOOL parent)BOOL: (  SHORT INT sum := 0;  FOR bit FROM LWB parent TO UPB parent DO    sum +:= ABS (parent[bit])  OD;  sum = 2); FOR generation FROM 0 WHILE  printf((\$"Generation "d": "\$, generation,         \$f(alive or dead)\$, universe,         \$l\$));# WHILE # generation < stop generation DO  [UPB universe]BOOL next universe;   # process the first event horizon manually #  next universe[1] := couple(universe[:2]);   # process the middle kingdom in a loop #  FOR bit FROM LWB universe + 1 TO UPB universe - 1 DO     next universe[bit] := couple(universe[bit-1:bit+1])  OD;    # process the last event horizon manually #  next universe[UPB universe] := couple(universe[UPB universe - 1: ]);  universe := next universeOD`
Output:
```Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________
```

## ALGOL W

Using a string to represent the cells and stopping when the next state is th same as the previous one.

`begin    string(20) state;    string(20) nextState;    integer    generation;    generation := 0;    state := "_###_##_#_#_#_#__#__";    while begin        write( i_w := 1, s_w := 1, "Generation ", generation, state );        nextState := "____________________";        for cPos := 1 until 18 do begin            string(3) curr;            curr := state( cPos - 1 // 3 );            nextState( cPos // 1 ) := if curr = "_##" or curr = "#_#" or curr = "##_" then "#" else "_"        end for_cPos ;        ( state not = nextState )    end do begin        state := nextState;        generation := generation + 1    end while_not_finishedend.`
Output:
```Generation 0 _###_##_#_#_#_#__#__
Generation 1 _#_#####_#_#_#______
Generation 2 __##___##_#_#_______
Generation 3 __##___###_#________
Generation 4 __##___#_##_________
Generation 5 __##____###_________
Generation 6 __##____#_#_________
Generation 7 __##_____#__________
Generation 8 __##________________
```

## Arturo

`evolve: function [arr][    ary: [0] ++ arr ++ [0]    ret: new []    loop 1..(size ary)-2 'i [        a: ary\[i-1]        b: ary\[i]        c: ary\[i+1]         if? 2 = a+b+c -> 'ret ++ 1        else          -> 'ret ++ 0    ]    ret] printIt: function [arr][    print replace replace join map arr => [to :string] "0" "_" "1" "#"] arr: [0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0]printIt arr newGen: evolve arrwhile [newGen <> arr][    arr: newGen    newGen: evolve arr    printIt newGen]`
Output:
```_###_##_#_#_#_#__#__
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________```

## AutoHotkey

ahk discussion

`n := 22, n1 := n+1, v0 := v%n1% := 0        ; set grid dimensions, and fixed cells Loop % n {                                  ; draw a line of checkboxes   v%A_Index% := 0   Gui Add, CheckBox, % "y10 w17 h17 gCheck x" A_Index*17-5 " vv" A_Index}Gui Add, Button, x+5 y6, step               ; button to step to next generationGui ShowReturn Check:   GuiControlGet %A_GuiControl%             ; set cells by the mouseReturn ButtonStep:                                 ; move to next generation   Loop % n      i := A_Index-1, j := i+2, w%A_Index% := v%i%+v%A_Index%+v%j% = 2   Loop % n      GuiControl,,v%A_Index%, % v%A_Index% := w%A_Index%Return GuiClose:                                   ; exit when GUI is closedExitApp`

## AWK

`#!/usr/bin/awk -fBEGIN {    edge = 1    ruleNum = 104 # 01101000    maxGen = 9    mark = "@"    space = "."    initialState = "[email protected]@@[email protected]@[email protected]@[email protected]@[email protected]"    width = length(initialState)    delete rules    delete state     initRules(ruleNum)    initState(initialState, mark)    for (g = 0; g < maxGen; g++) {        showState(g, mark, space)        nextState()    }    showState(g, mark, space)} function nextState(    newState, i, n) {    delete newState    for (i = 1; i < width - 1; i++) {        n = getRuleNum(i)        newState[i] = rules[n]    }    for (i = 0; i < width; i++) { # copy, can't assign arrays        state[i] = newState[i]    }} # Convert a three cell neighborhood from binary to decimalfunction getRuleNum(i,    rn, j, p) {    rn = 0    for (j = -1; j < 2; j++) {        p = i + j        rn = rn * 2 + (p < 0 || p > width ? edge : state[p])    }    return rn} function showState(gen, mark, space,    i) {    printf("%3d: ", gen)    for (i = 1; i <= width; i++) {        printf(" %s", (state[i] ? mark : space))    }    print ""} # Make state transition lookup table from rule number.function initRules(ruleNum,   i, r) {    delete rules;    r = ruleNum    for (i = 0; i < 8; i++) {        rules[i] = r % 2        r = int(r / 2)    }} function initState(init, mark,    i) {    delete state    srand()    for (i = 0; i < width; i++) {        state[i] = (substr(init, i, 1) == mark ? 1 : 0) # Given an initial string.        # state[int(width/2)] = '@'  # middle cell        # state[i] = int(rand() * 100) < 30 ? 1 : 0 # 30% of cells    }} `
Output:
```  0:  . @ @ @ . @ @ . @ . @ . @ . @ . . @ . .
1:  . @ . @ @ @ @ @ . @ . @ . @ . . . . . .
2:  . . @ @ . . . @ @ . @ . @ . . . . . . .
3:  . . @ @ . . . @ @ @ . @ . . . . . . . .
4:  . . @ @ . . . @ . @ @ . . . . . . . . .
5:  . . @ @ . . . . @ @ @ . . . . . . . . .
6:  . . @ @ . . . . @ . @ . . . . . . . . .
7:  . . @ @ . . . . . @ . . . . . . . . . .
8:  . . @ @ . . . . . . . . . . . . . . . .
9:  . . @ @ . . . . . . . . . . . . . . . .
```
`Another new solution (twice size as previous solution) :cat automata.awk : #!/usr/local/bin/gawk -f # User defined functionsfunction ASCII_to_Binary(str_) {	gsub("_","0",str_); gsub("@","1",str_)	return str_} function Binary_to_ASCII(bit_) {	gsub("0","_",bit_); gsub("1","@",bit_)	return bit_} function automate(b1,b2,b3) {	a = and(b1,b2,b3)	b = or(b1,b2,b3)	c = xor(b1,b2,b3)	d = a + b + c	return d == 1 ? 1 : 0} # For each line in input do{str_ = \$0gen = 0taille = length(str_)print "0: " str_do {	gen ? str_previous = str_ : str_previous = ""	gen += 1	str_ = ASCII_to_Binary(str_)	split(str_,tab,"")	str_ = and(tab[1],tab[2])	for (i=1; i<=taille-2; i++) {		str_ = str_ automate(tab[i],tab[i+1],tab[i+2])		}	str_ = str_ and(tab[taille-1],tab[taille])	print gen ": " Binary_to_ASCII(str_)   } while (str_ != str_previous)} `
Output:
```\$ echo "[email protected]@@[email protected]@[email protected]@[email protected]@[email protected]" | awk -f automata.awk
0: [email protected]@@[email protected]@[email protected]@[email protected]@[email protected]
1: [email protected][email protected]@@@@[email protected][email protected][email protected]______
2: [email protected]@[email protected]@[email protected][email protected]_______
3: [email protected]@[email protected]@@[email protected]________
4: [email protected]@[email protected][email protected]@_________
5: [email protected]@[email protected]@@_________
6: [email protected]@[email protected][email protected]_________
7: [email protected]@[email protected]__________
8: [email protected]@________________
9: [email protected]@________________
```

## BASIC

Works with: QBasic version 1.1
Works with: QuickBasic version 4.5
Translation of: Java
`DECLARE FUNCTION life\$ (lastGen\$)DECLARE FUNCTION getNeighbors! (group\$)CLSstart\$ = "_###_##_#_#_#_#__#__"numGens = 10FOR i = 0 TO numGens - 1	PRINT "Generation"; i; ": "; start\$	start\$ = life\$(start\$)NEXT i FUNCTION getNeighbors (group\$)		ans = 0		IF (MID\$(group\$, 1, 1) = "#") THEN ans = ans + 1		IF (MID\$(group\$, 3, 1) = "#") THEN ans = ans + 1		getNeighbors = ansEND FUNCTION FUNCTION life\$ (lastGen\$)		newGen\$ = ""		FOR i = 1 TO LEN(lastGen\$)			neighbors = 0			IF (i = 1) THEN 'left edge				IF MID\$(lastGen\$, 2, 1) = "#" THEN					neighbors = 1				ELSE					neighbors = 0				END IF			ELSEIF (i = LEN(lastGen\$)) THEN 'right edge				IF MID\$(lastGen\$, LEN(lastGen\$) - 1, 1) = "#" THEN					neighbors = 1				ELSE					neighbors = 0				END IF			ELSE 'middle				neighbors = getNeighbors(MID\$(lastGen\$, i - 1, 3))			END IF 			IF (neighbors = 0) THEN 'dies or stays dead with no neighbors				newGen\$ = newGen\$ + "_"			END IF			IF (neighbors = 1) THEN 'stays with one neighbor				newGen\$ = newGen\$ + MID\$(lastGen\$, i, 1)			END IF			IF (neighbors = 2) THEN 'flips with two neighbors				IF MID\$(lastGen\$, i, 1) = "#" THEN					newGen\$ = newGen\$ + "_"				ELSE					newGen\$ = newGen\$ + "#"				END IF			END IF		NEXT i		life\$ = newGen\$END FUNCTION`
Output:
```Generation 0 : _###_##_#_#_#_#__#__
Generation 1 : _#_#####_#_#_#______
Generation 2 : __##___##_#_#_______
Generation 3 : __##___###_#________
Generation 4 : __##___#_##_________
Generation 5 : __##____###_________
Generation 6 : __##____#_#_________
Generation 7 : __##_____#__________
Generation 8 : __##________________
Generation 9 : __##________________```

### FreeBASIC

`#define SIZE 640 randomize timer dim as ubyte arr(0 to SIZE-1, 0 to 1)dim as uinteger ifor i = 0 to SIZE - 1   'initialise array with zeroes and ones    arr(i, 0)=int(rnd+0.5)next i screen 12    'display graphically dim as string ch=" "dim as uinteger j = 0, cur = 0, nxt, prv, neighwhile not ch = "q" or ch = "Q"    for i = 0 to SIZE - 1        pset(i, j), 8+7*arr(i,cur)   'print off cells as grey, on cells as bright white        nxt = (i + 1) mod SIZE        prv = (i - 1)        if prv < 0 then prv = SIZE - 1   'let's have a wrap-around array for fun        neigh = arr(prv, cur) + arr(nxt, cur)        if arr(i, cur) = 0 then    'evolution rules            if neigh = 2 then                arr(i, 1-cur) = 1            else                arr(i, 1-cur) = 0            end if        else            if neigh = 0 or neigh = 2 then                arr(i, 1-cur) = 0            else                arr(i, 1-cur) = 1            end if        end if    next i    j = j + 1    cur = 1 - cur    do        ch = inkey        if ch <> "" then exit do   'press any key to advance the sim                                   'or Q to exit    loopwend`

### Sinclair ZX81 BASIC

Works with the unexpanded (1k RAM) ZX81.

` 10 LET N\$="01110110101010100100" 20 LET G=1 30 PRINT N\$ 40 LET O\$=N\$ 50 LET N\$="" 60 PRINT AT 0,28;G 70 LET N=0 80 FOR I=1 TO LEN O\$ 90 IF I=1 THEN GOTO 120100 LET N=VAL O\$(I-1)110 IF I=LEN O\$ THEN GOTO 130120 LET N=N+VAL O\$(I+1)130 IF N=0 THEN LET N\$=N\$+"0"140 IF N=1 THEN LET N\$=N\$+O\$(I)150 IF N=2 THEN LET N\$=N\$+STR\$ NOT VAL O\$(I)160 PRINT AT 0,I-1;N\$(I)170 NEXT I180 LET G=G+1190 IF N\$<>O\$ THEN GOTO 40`
Output:

The program overwrites each cell on the screen as it updates it (which it does quite slowly—there is no difficulty about watching what it is doing), with a counter to the right showing the generation it is currently working on. When it is part of the way through, for example, the display looks like this:

`00110001011000000000        5`

It halts when a stable state has been reached:

`00110000000000000000        9`

## BASIC256

`arraybase 1dim start = {0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0}dim sgtes(start[?]+1) for k = 0 to 9    print "Generation "; k; ": ";    for j = 0 to start[?]-1         if start[j] then print "#"; else print "_";        if start[j-1] + start[j] + start[j+1] = 2 then sgtes[j] = 1 else sgtes[j] = 0    next j    print    for j = 0 to start[?]-1        start[j] = sgtes[j]    next jnext k`

## Batch File

This implementation will not stop showing generations, unless the cellular automata is already stable.

`@echo offsetlocal enabledelayedexpansion::THE MAIN THINGcall :one-dca __###__##_#_##_###__######_###_#####_#__##_____#_#_#######__pause>nulexit /b::/THE MAIN THING::THE PROCESSOR:one-dcaecho.&set numchars=0&set proc=%1::COUNT THE NUMBER OF CHARSset bef=%proc:_=_,%set bef=%bef:#=#,%set bef=%bef:~0,-1%for %%x in (%bef%) do set /a numchars+=1 set /a endchar=%numchars%-1:nextgenecho.   ^| %proc% ^|set currnum=0set newgen=:editeachchar	set neigh=0	set /a testnum2=%currnum%+1	set /a testnum1=%currnum%-1	if %currnum%==%endchar% (		set testchar=!proc:~%testnum1%,1!		if !testchar!==# (set neigh=1)	) else (		if %currnum%==0 (			set testchar=%proc:~1,1%			if !testchar!==# (set neigh=1)		) else (			set testchar1=!proc:~%testnum1%,1!			set testchar2=!proc:~%testnum2%,1!			if !testchar1!==# (set /a neigh+=1)			if !testchar2!==# (set /a neigh+=1)		)	)	if %neigh%==0 (set newgen=%newgen%_)	if %neigh%==1 (		set testchar=!proc:~%currnum%,1!		set newgen=%newgen%!testchar!	)	if %neigh%==2 (		set testchar=!proc:~%currnum%,1!		if !testchar!==# (set newgen=%newgen%_) else (set newgen=%newgen%#)	)if %currnum%==%endchar% (goto :cond) else (set /a currnum+=1&goto :editeachchar) :condif %proc%==%newgen% (echo.&echo          ...The sample is now stable.&goto :EOF)set proc=%newgen%goto :nextgen::/THE (LLLLLLOOOOOOOOOOOOONNNNNNNNGGGGGG.....) PROCESSOR`
Output:
```   | __###__##_#_##_###__######_###_#####_#__##_____#_#_#######__ |
| __#_#__###_#####_#__#____###_###___##___##______#_##_____#__ |
| ___#___#_###___##________#_###_#___##___##_______###________ |
| ________##_#___##_________##_##____##___##_______#_#________ |
| ________###____##_________#####____##___##________#_________ |
| ________#_#____##_________#___#____##___##__________________ |
| _________#_____##__________________##___##__________________ |
| _______________##__________________##___##__________________ |

...The sample is now stable.```

## BBC BASIC

`      DIM rule\$(7)      rule\$() = "0", "0", "0", "1", "0", "1", "1", "0"       now\$ = "01110110101010100100"       FOR generation% = 0 TO 9        PRINT "Generation " ; generation% ":", now\$        next\$ = ""        FOR cell% = 1 TO LEN(now\$)          next\$ += rule\$(EVAL("%"+MID\$("0"+now\$+"0", cell%, 3)))        NEXT cell%        SWAP now\$, next\$      NEXT generation%`
Output:
```Generation 0:       01110110101010100100
Generation 1:       01011111010101000000
Generation 2:       00110001101010000000
Generation 3:       00110001110100000000
Generation 4:       00110001011000000000
Generation 5:       00110000111000000000
Generation 6:       00110000101000000000
Generation 7:       00110000010000000000
Generation 8:       00110000000000000000
Generation 9:       00110000000000000000```

## Befunge

`v                                                                                                          " !!! !! ! ! ! !  !  "                                                          ,*25                    <v "                    "                                                           ,*25,,,,,,,,,,,,,,,,,,,,<v "                    "                                                            ,*25,,,,,,,,,,,,,,,,,,,,<v "                    "                                                             ,*25,,,,,,,,,,,,,,,,,,,,<v "                    "                                                              ,*25,,,,,,,,,,,,,,,,,,,,<v "                    "                                                               ,*25,,,,,,,,,,,,,,,,,,,,<v "                    "                                                                ,*25,,,,,,,,,,,,,,,,,,,,<v "                    "                                                                 ,*25,,,,,,,,,,,,,,,,,,,,<v "                    "                                                                  ,*25,,,,,,,,,,,,,,,,,,,,<v                                                                      v\$<                @,*25,,,,,,,,,,,,,,,,,,,,<>110p3>:1-10gg" "-4* \:10gg" "-2* \:1+10gg" "-\:54*1+`#v_20p++ :2`#v_ >:4`#v_> >\$" "v                                                                                        >:3`#^_v>:6`|                                ^                                                >\$\$\$\$320p10g1+:9`v >    >\$"!"> 20g10g1+p 20g1+:20p       ^                                                                v_10p10g                                                                                                  >                                 ^`

## Bracmat

`  ( ( evolve    =   n z      .   @( !arg           : %?n ? @?z           :   ?               ( (   ( 000                     | 001                     | 010                     | 100                     | 111                     )                   & 0 !n:?n                 |   (011|101|110)                   & 1 !n:?n                 )               & ~`               )               ?           )        | rev\$(str\$(!z !n))    )  & 11101101010101001001:?S  & :?seen  &   whl    ' ( ~(!seen:? !S ?)      & out\$!S      & !S !seen:?seen      & evolve\$!S:?S      )  );`
Output:
```11101101010101001001
10111110101010000001
11100011010100000001
10100011101000000001
11000010110000000001
11000001110000000001
11000001010000000001
11000000100000000001
11000000000000000001```

## C

`#include <stdio.h>#include <string.h> char trans[] = "___#_##_"; #define v(i) (cell[i] != '_')int evolve(char cell[], char backup[], int len){	int i, diff = 0; 	for (i = 0; i < len; i++) {		/* use left, self, right as binary number bits for table index */		backup[i] = trans[ v(i-1) * 4 + v(i) * 2 + v(i + 1) ];		diff += (backup[i] != cell[i]);	} 	strcpy(cell, backup);	return diff;} int main(){	char	c[] = "_###_##_#_#_#_#__#__\n",		b[] = "____________________\n"; 	do { printf(c + 1); } while (evolve(c + 1, b + 1, sizeof(c) - 3));	return 0;}`
Output:
```###_##_#_#_#_#__#__
#_#####_#_#_#______
_##___##_#_#_______
_##___###_#________
_##___#_##_________
_##____###_________
_##____#_#_________
_##_____#__________
_##________________```

Similar to above, but without a backup string:

`#include <stdio.h> char trans[] = "___#_##_"; int evolve(char c[], int len){	int i, diff = 0;#	define v(i) ((c[i] & 15) == 1)#	define each for (i = 0; i < len; i++) 	each c[i]  = (c[i] == '#');	each c[i] |= (trans[(v(i-1)*4 + v(i)*2 + v(i+1))] == '#') << 4;	each diff += (c[i] & 0xf) ^ (c[i] >> 4);	each c[i]  = (c[i] >> 4) ? '#' : '_'; #	undef each#	undef v	return diff;} int main(){	char c[] = "_###_##_#_#_#_#__#__\n"; 	do { printf(c + 1); } while (evolve(c + 1, sizeof(c) - 3));	return 0;}`

## C#

`using System;using System.Collections.Generic; namespace prog{	class MainClass	{			const int n_iter = 10;		static int[] f = { 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0 }; 		public static void Main (string[] args)		{			for( int i=0; i<f.Length; i++ )				Console.Write( f[i]==0 ? "-" : "#" );			Console.WriteLine("");			 			int[] g = new int[f.Length];			for( int n=n_iter; n!=0; n-- )			{				for( int i=1; i<f.Length-1; i++ )				{					if ( (f[i-1] ^ f[i+1]) == 1 ) g[i] = f[i];					else if ( f[i] == 0 && (f[i-1] & f[i+1]) == 1 ) g[i] = 1;					else g[i] = 0;				}				g[0] = ( (f[0] & f[1]) == 1 ) ? 1 : 0;				g[g.Length-1] = ( (f[f.Length-1] & f[f.Length-2]) == 1 ) ? 1 : 0; 				int[] tmp = f;				f = g;				g = tmp; 				for( int i=0; i<f.Length; i++ )					Console.Write( f[i]==0 ? "-" : "#" );				Console.WriteLine("");			}					}	}}`

## C++

Uses std::bitset for efficient packing of bit values.

`#include <iostream>#include <bitset>#include <string> const int ArraySize = 20;const int NumGenerations = 10;const std::string Initial = "0011101101010101001000"; int main(){    // + 2 for the fixed ends of the array    std::bitset<ArraySize + 2> array(Initial);     for(int j = 0; j < NumGenerations; ++j)    {        std::bitset<ArraySize + 2> tmpArray(array);        for(int i = ArraySize; i >= 1 ; --i)        {            if(array[i])                std::cout << "#";            else                std::cout << "_";            int val = (int)array[i-1] << 2 | (int)array[i] << 1 | (int)array[i+1];            tmpArray[i] = (val == 3 || val == 5 || val == 6);        }        array = tmpArray;        std::cout << std::endl;    }}`
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________```

## Ceylon

`shared abstract class Cell(character) of alive | dead {	shared Character character;	string => character.string;	shared formal Cell opposite;} shared object alive extends Cell('#') {	opposite => dead;}shared object dead extends Cell('_') {	opposite => alive;} shared Map<Character, Cell> cellsByCharacter = map { for (cell in `Cell`.caseValues) cell.character->cell }; shared class Automata1D({Cell*} initialCells) {  	value permanentFirstCell = initialCells.first else dead;	value permanentLastCell = initialCells.last else dead; 	value cells = Array { *initialCells.rest.exceptLast }; 	shared Boolean evolve() { 		value newCells = Array {			for (index->cell in cells.indexed)			let (left = cells[index - 1] else permanentFirstCell, 				right = cells[index + 1] else permanentLastCell,				neighbours = [left, right], 				bothAlive = neighbours.every(alive.equals),				bothDead = neighbours.every(dead.equals))			if (bothAlive)			then cell.opposite			else if (cell == alive && bothDead)			then dead			else cell		}; 		if (newCells == cells) {			return false;		} 		newCells.copyTo(cells);		return true;	} 	string => permanentFirstCell.string + "".join(cells) + permanentLastCell.string;} shared Automata1D? automata1d(String string) => 		let (cells = string.map((Character element) => cellsByCharacter[element]))		if (cells.every((Cell? element) => element exists)) 		then Automata1D(cells.coalesced) 		else null; shared void run() { 	assert (exists automata = automata1d("__###__##_#_##_###__######_###_#####_#__##_____#_#_#######__")); 	variable value generation = 0;	print("generation ``generation`` ``automata``");	while (automata.evolve() && generation<10) {		print("generation `` ++generation `` ``automata``");	}}`

## Clojure

`(ns one-dimensional-cellular-automata  (:require (clojure.contrib (string :as s)))) (defn next-gen [cells]  (loop [cs cells ncs (s/take 1 cells)]    (let [f3 (s/take 3 cs)]      (if (= 3 (count f3))        (recur (s/drop 1 cs)               (str ncs (if (= 2 (count (filter #(= \# %) f3))) "#" "_")))        (str ncs (s/drop 1 cs)))))) (defn generate [n cells]  (if (= n 0)    '()    (cons cells (generate (dec n) (next-gen cells))))) `
`one-dimensional-cellular-automata> (doseq [cells (generate 9 "_###_##_#_#_#_#__#__")]  (println cells))_###_##_#_#_#_#__#___#_#####_#_#_#________##___##_#_#_________##___###_#__________##___#_##___________##____###___________##____#_#___________##_____#____________##________________nil `

Another way:

`#!/usr/bin/env lein-exec (require '[clojure.string :as str]) (def first-genr "_###_##_#_#_#_#__#__") (def hospitable #{"_##"                  "##_"                  "#_#"}) (defn compute-next-genr  [genr]  (let [genr      (str "_" genr "_")        groups    (map str/join (partition 3 1 genr))        next-genr (for [g groups]                    (if (hospitable g) \# \_))]    (str/join next-genr))) ;; ---------------- main -----------------(loop [g  first-genr       i  0]  (if (not= i 10)    (do (println g)        (recur (compute-next-genr g)               (inc i)))))`

Yet another way, easier to understand

` (def rules {    [0 0 0] 0    [0 0 1] 0    [0 1 0] 0    [0 1 1] 1    [1 0 0] 0    [1 0 1] 1    [1 1 0] 1    [1 1 1] 0  }) (defn nextgen [gen]  (concat [0]           (->> gen               (partition 3 1)               (map vec)               (map rules))          [0])) ; Output time!(doseq [g (take 10 (iterate nextgen [0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0]))]  (println g)) `

## COBOL

`  Identification division.                                         Program-id. rc-1d-cell.                                           Data division.                                                   Working-storage section.                                         *> "Constants."                                                   01 max-gens            pic  999  value   9.                      01 state-width         pic   99  value  20.                      01 state-table-init    pic x(20) value "[email protected]@@[email protected]@[email protected]@[email protected]@[email protected]".   01 alive               pic    x  value "@".                      01 dead                pic    x  value ".".                      *> The current state.                                             01 state-gen           pic  999  value   0.                      01 state-row.                                                      05 state-row-gen   pic zz9.                                    05 filler          pic  xx   value ": ".                       05 state-table.                                                    10 state-cells pic   x   occurs 20 times.               *> The new state.                                                01 new-state-table.                                                05 new-state-cells pic   x   occurs 20 times.               *> Pointer into cell table during generational production.       01 cell-index          pic   99.                                   88 at-beginning    value  1.                                   88 is-inside       values 2 thru 19.                           88 at-end          value 20.                                *> The cell's neighborhood.                          01 neighbor-count-def.                             03 neighbor-count      pic   9.     88 is-comfy        value 1.                         88 is-ripe         value 2.                      Procedure division.                                     Perform Init-state-table.                           Perform max-gens times                                  perform Display-row                                 perform Next-state                              end-perform.                                        Perform Display-row.                                Stop run.                                        Display-row.                                            Move state-gen to state-row-gen.          Display state-row.                    *> Determine who lives and who dies.       Next-state.                                   Add 1 to state-gen.                       Move state-table to new-state-table.       Perform with test after                       varying cell-index from 1 by 1            until at-end                              perform Count-neighbors                   perform Die-off                                      perform New-births                               end-perform                                           move new-state-table to state-table.             *> Living cell with wrong number of neighbors...      Die-off.                                                 if state-cells(cell-index) =                         alive and not is-comfy             then move dead to new-state-cells(cell-index)                end-if                                                           .                                                            *> Empty cell with exactly two neighbors are...                   New-births.                                                          if state-cells(cell-index) = dead and is-ripe         then move alive to new-state-cells(cell-index)               end-if                                                          .                                                           *> How many living neighbors does a cell have?                    Count-neighbors.                                                     Move 0 to neighbor-count                             if at-beginning or at-end then                                       add 1 to neighbor-count                           else                                                               if is-inside and state-cells(cell-index - 1) = alive               then                                                                   add 1 to neighbor-count                            end-if                                                             if is-inside and state-cells(cell-index + 1) = alive               then                                                                   add 1 to neighbor-count                            end-if                                                            end-if                                                             .                                                              *> String is easier to enter, but table is easier to work with,    *> so move each character of the initialization string to the      *> state table.                                                      Init-state-table.                                                      Perform with test after                             varying cell-index from 1 by 1                  until at-end                                    move state-table-init(cell-index:1)               to state-cells(cell-index)                 end-perform      .                                                                              `
Output:
```  0: [email protected]@@[email protected]@[email protected]@[email protected]@[email protected]
1: [email protected]@@@@@[email protected]@[email protected]
2: [email protected]@[email protected]@[email protected]@.......
3: [email protected]@[email protected]@@[email protected]
4: [email protected]@[email protected]@@.........
5: [email protected]@[email protected]@@.........
6: [email protected]@[email protected]@.........
7: [email protected]@[email protected]
8: [email protected]@................
9: [email protected]@................```

=pre>###_##_#_#_#_#__#__

1. _#####_#_#_#______

_##___##_#_#_______ _##___###_#________ _##___#_##_________ _##____###_________ _##____#_#_________ _##_____#__________ _##________________=CoffeeScript==

` # We could cheat and count the bits, but let's keep this general.# . = dead, # = alive, middle cells survives iff one of the configurations# below is satisified.survival_scenarios = [  '.##' # happy neighbors  '#.#' # birth  '##.' # happy neighbors] b2c = (b) -> if b then '#' else '.' cell_next_gen = (left_alive, me_alive, right_alive) ->  fingerprint = b2c(left_alive) + b2c(me_alive) + b2c(right_alive)  fingerprint in survival_scenarios cells_for_next_gen = (cells) ->  # This function assumes a finite array, i.e. cells can't be born outside  # the original array.  (cell_next_gen(cells[i-1], cells[i], cells[i+1]) for i in [0...cells.length]) display = (cells) ->  (b2c(is_alive) for is_alive in cells).join '' simulate = (cells) ->  while true    console.log display cells    new_cells = cells_for_next_gen cells    break if display(cells) == display(new_cells)    cells = new_cells  console.log "equilibrium achieved" simulate (c == '#' for c in ".###.##.#.#.#.#..#..") `
Output:
```> coffee cellular_automata.coffee
.###.##.#.#.#.#..#..
.#.#####.#.#.#......
..##...##.#.#.......
..##...###.#........
..##...#.##.........
..##....###.........
..##....#.#.........
..##.....#..........
..##................
equilibrium achieved
```

## Common Lisp

Based upon the Ruby version.

`(defun value (x)  (assert (> (length x) 1))  (coerce x 'simple-bit-vector)) (defun count-neighbors-and-self (value i)  (flet ((ref (i)           (if (array-in-bounds-p value i)               (bit value i)               0)))    (declare (inline ref))    (+ (ref (1- i))       (ref i)       (ref (1+ i))))) (defun next-cycle (value)  (let ((new-value (make-array (length value) :element-type 'bit)))    (loop for i below (length value)          do (setf (bit new-value i)                   (if (= 2 (count-neighbors-and-self value i))                       1                       0)))    new-value)) (defun print-world (value &optional (stream *standard-output*))  (loop for i below (length value)        do (princ (if (zerop (bit value i)) #\. #\#)                  stream))  (terpri stream))`
`CL-USER> (loop for previous-value = nil then value               for value = #*01110110101010100100 then (next-cycle value)               until (equalp value previous-value)               do (print-world value)).###.##.#.#.#.#..#...#.#####.#.#.#........##...##.#.#.........##...###.#..........##...#.##...........##....###...........##....#.#...........##.....#............##................`

## D

`void main() {   import std.stdio, std.algorithm;    enum nGenerations = 10;   enum initial = "0011101101010101001000";   enum table = "00010110";    char[initial.length + 2] A = '0', B = '0';   A[1 .. \$-1] = initial;   foreach (immutable _; 0 .. nGenerations) {      foreach (immutable i; 1 .. A.length - 1) {         write(A[i] == '0' ? '_' : '#');         const val = (A[i-1]-'0' << 2) | (A[i]-'0' << 1) | (A[i+1]-'0');         B[i] = table[val];      }      A.swap(B);      writeln;   }}`
Output:
```__###_##_#_#_#_#__#___
__#_#####_#_#_#_______
___##___##_#_#________
___##___###_#_________
___##___#_##__________
___##____###__________
___##____#_#__________
___##_____#___________
___##_________________
___##_________________```

### Alternative Version

Translation of: Raku
`void main() {    import std.stdio, std.algorithm, std.range;     auto A = "_###_##_#_#_#_#__#__".map!q{a == '#'}.array;    auto B = A.dup;     do {        A.map!q{ "_#"[a] }.writeln;        A.zip(A.cycle.drop(1), A.cycle.drop(A.length - 1))        .map!(t => [t[]].sum == 2).copy(B);        A.swap(B);    } while (A != B);}`
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________```

### Alternative Version II

This version saves memory representing the state in an array of bits. For a higher performance a SWAR approach should be tried.

Translation of: C++
`void main() {    import std.stdio, std.algorithm, std.range, std.bitmanip;     immutable initial = "__###_##_#_#_#_#__#___";    enum nGenerations = 10;    BitArray A, B;    A.init(initial.map!(c => c == '#').array);    B.length = initial.length;     foreach (immutable _; 0 .. nGenerations) {        //A.map!(b => b ? '#' : '_').writeln;        //foreach (immutable i, immutable b; A) {        foreach (immutable i; 1 .. A.length - 1) {            "_#"[A[i]].write;            immutable val = (uint(A[i - 1]) << 2) |                            (uint(A[i])     << 1) |                             uint(A[i + 1]);            B[i] = val == 3 || val == 5 || val == 6;        }         writeln;        A.swap(B);    }}`

The output is the same as the second version.

## DWScript

`const ngenerations = 10;const table = [0, 0, 0, 1, 0, 1, 1, 0]; var a := [0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0];var b := a; var i, j : Integer;for i := 1 to ngenerations do begin   for j := a.low+1 to a.high-1 do begin      if a[j] = 0 then         Print('_')      else Print('#');      var val := (a[j-1] shl 2) or (a[j] shl 1) or a[j+1];      b[j] := table[val];   end;   var tmp := a;   a := b;   b := tmp;   PrintLn('');end; `
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________```

## Déjà Vu

`new-state size:	0 ]	repeat size:		random-range 0 2	[ 0 update s1 s2:	for i range 1 - len s1 2:		s1! -- i		s1!    i		s1! ++ i		+ +		set-to s2 i = 2	s2 s1 print-state s:	for i range 1 - len s 2:		!print\ s! i	!print "" same-state s1 s2:	for i range 1 - len s1 2:		if /= s1! i s2! i:			return false	true run size:	new-state size	new-state size	while true:		update		print-state over		if same-state over over:			return print-state drop run 60`
Output:
```001110011010110111001111110111011111010011000001010111111100
001010011101111101001000011101110001100011000000101100000100
000100010111000110000000010111010001100011000000011100000000
000000001101000110000000001101100001100011000000010100000000
000000001110000110000000001111100001100011000000001000000000
000000001010000110000000001000100001100011000000000000000000
000000000100000110000000000000000001100011000000000000000000
000000000000000110000000000000000001100011000000000000000000
000000000000000110000000000000000001100011000000000000000000```

## E

`def step(state, rule) {    var result := state(0, 1) # fixed left cell    for i in 1..(state.size() - 2) {        # Rule function receives the substring which is the neighborhood        result += E.toString(rule(state(i-1, i+2)))    }    result += state(state.size() - 1) # fixed right cell    return result} def play(var state, rule, count, out) {    out.print(`0 | \$state\$\n`)    for i in 1..count {        state := step(state, rosettaRule)        out.print(`\$i | \$state\$\n`)    }    return state}`
`def rosettaRule := [    "   " => " ",    "  #" => " ",    " # " => " ",    " ##" => "#",    "#  " => " ",    "# #" => "#",    "## " => "#",    "###" => " ",].get ? play("  ### ## # # # #  #   ", rosettaRule, 9, stdout)0 |   ### ## # # # #  #   1 |   # ##### # # #       2 |    ##   ## # #        3 |    ##   ### #         4 |    ##   # ##          5 |    ##    ###          6 |    ##    # #          7 |    ##     #           8 |    ##                 9 |    ##                 # value: "   ##                 "`

## Eiffel

` class	APPLICATION create	make feature 	make			-- First 10 states of the cellular automata.		local			r: RANDOM			automata: STRING		do			create r.make			create automata.make_empty			across				1 |..| 10 as c			loop				if r.double_item < 0.5 then					automata.append ("0")				else					automata.append ("1")				end				r.forth			end			across				1 |..| 10 as c			loop				io.put_string (automata + "%N")				automata := update (automata)			end		end 	update (s: STRING): STRING			-- Next state of the cellular automata 's'.		require			enough_states: s.count > 1		local			i: INTEGER		do			create Result.make_empty				-- Dealing with the left border.			if s [1] = '1' and s [2] = '1' then				Result.append ("1")			else				Result.append ("0")			end				-- Dealing with the middle cells.			from				i := 2			until				i = s.count			loop				if (s [i] = '0' and (s [i - 1] = '0' or (s [i - 1] = '1' and s [i + 1] = '0'))) or ((s [i] = '1') and ((s [i - 1] = '1' and s [i + 1] = '1') or (s [i - 1] = '0' and s [i + 1] = '0'))) then					Result.append ("0")				else					Result.append ("1")				end				i := i + 1			end				-- Dealing with the right border.			if s [s.count] = '1' and s [s.count - 1] = '1' then				Result.append ("1")			else				Result.append ("0")			end		ensure			has_same_length: s.count = Result.count		end end `
Output:
```1011101110
0110111010
0111101100
0100111100
0000100100
0000000000
0000000000
0000000000
0000000000
0000000000
```

## Elixir

Translation of: Ruby
`defmodule RC do  def run(list, gen \\ 0) do    print(list, gen)    next = evolve(list)    if next == list, do: print(next, gen+1), else: run(next, gen+1)  end   defp evolve(list), do: evolve(Enum.concat([[0], list, [0]]), [])   defp evolve([a,b,c],      next), do: Enum.reverse([life(a,b,c) | next])  defp evolve([a,b,c|rest], next), do: evolve([b,c|rest], [life(a,b,c) | next])   defp life(a,b,c), do: (if a+b+c == 2, do: 1, else: 0)   defp print(list, gen) do    str = "Generation #{gen}: "    IO.puts Enum.reduce(list, str, fn x,s -> s <> if x==0, do: ".", else: "#" end)  endend RC.run([0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0])`
Output:
```Generation 0: .###.##.#.#.#.#..#..
Generation 1: .#.#####.#.#.#......
Generation 2: ..##...##.#.#.......
Generation 3: ..##...###.#........
Generation 4: ..##...#.##.........
Generation 5: ..##....###.........
Generation 6: ..##....#.#.........
Generation 7: ..##.....#..........
Generation 8: ..##................
Generation 9: ..##................
```

## Elm

`import Maybe exposing (withDefault)import List exposing (length, tail, reverse, concat, head, append, map3)import Html exposing (Html, div, h1, text)import String exposing (join)import Svg exposing (svg)import Svg.Attributes exposing (version, width, height, viewBox,cx,cy, fill, r)import Html.App exposing (program)import Random exposing (step, initialSeed, bool, list)import Matrix exposing (fromList, mapWithLocation, flatten)  -- chendrix/elm-matriximport Time exposing (Time, second, every) type alias Model = { history : List (List Bool)                   , cols : Int                   , rows : Int                   } view : Model -> Html Msgview model =   let     circleInBox (row,col) value =       if value       then [ Svg.circle [ r "0.3"                        , fill ("purple")                        , cx (toString (toFloat col + 0.5))                        , cy (toString (toFloat row + 0.5))                        ]                                    []             ]      else []     showHistory model =       model.history         |> reverse        |> fromList        |> mapWithLocation circleInBox         |> flatten         |> concat   in    div []        [ h1 [] [text "One Dimensional Cellular Automata"]        , svg [ version "1.1"              , width "700"              , height "700"              , viewBox (join " "                           [ 0 |> toString                           , 0 |> toString                           , model.cols |> toString                           , model.rows |> toString                           ]                        )              ]               (showHistory model)        ] update : Msg -> Model -> (Model, Cmd Msg)update msg model =   if length model.history == model.rows  then (model, Cmd.none)  else    let s1 = model.history |> head |> withDefault []        s0 = False :: s1        s2 = append (tail s1 |> withDefault []) [False]         gen d0 d1 d2 =           case (d0,d1,d2) of            (False,  True,  True) -> True            ( True, False,  True) -> True            ( True,  True, False) -> True            _                     -> False         updatedHistory = map3 gen s0 s1 s2 :: model.history        updatedModel = {model | history = updatedHistory}    in (updatedModel, Cmd.none)  init : Int -> (Model, Cmd Msg)init n =   let gen1 = fst (step (list n bool) (initialSeed 34))  in ({ history = [gen1], rows = n, cols= n }, Cmd.none) type Msg = Tick Time  subscriptions model = every (0.2 * second) Tick main = program          {  init = init 40         ,  view = view         ,  update = update         ,  subscriptions = subscriptions         }`

## Erlang

` -module(ca).-compile(export_all). run(N,G) ->    run(N,G,0). run(GN,G,GN) ->    io:fwrite("~B: ",[GN]),    print(G);run(N,G,GN) ->    io:fwrite("~B: ",[GN]),    print(G),    run(N,next(G),GN+1). print([]) ->    io:fwrite("~n");print([0|T]) ->    io:fwrite("_"),    print(T);print([1|T]) ->    io:fwrite("#"),    print(T). next([]) ->    [];next([_]) ->    [0];next([H,1|_]=G) ->    next(G,[H]);next([_|_]=G) ->    next(G,[0]). next([],Acc) ->    lists:reverse(Acc);next([0,_],Acc) ->       next([],[0|Acc]);next([1,X],Acc) ->       next([],[X|Acc]);next([0,X,0|T],Acc) ->    next([X,0|T],[0|Acc]);next([1,X,0|T],Acc) ->    next([X,0|T],[X|Acc]);next([0,X,1|T],Acc) ->    next([X,1|T],[X|Acc]);next([1,0,1|T],Acc) ->    next([0,1|T],[1|Acc]);next([1,1,1|T],Acc) ->    next([1,1|T],[0|Acc]). `

Example execution:

` 44> ca:run(9,[0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0]).0: __###_##_#_#_#_#__#___1: __#_#####_#_#_#_______2: ___##___##_#_#________3: ___##___###_#_________4: ___##___#_##__________5: ___##____###__________6: ___##____#_#__________7: ___##_____#___________8: ___##_________________9: ___##_________________ `

## ERRE

` PROGRAM ONEDIM_AUTOMATA ! for rosettacode.org! !VAR I,J,N,W,K !\$DYNAMICDIM X[0],X2[0] BEGIN    DATA(20,0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0)    PRINT(CHR\$(12);)   N=20      ! number of generation required   READ(W)   !\$DIM X[W+1],X2[W+1]   FOR I=1 TO W DO      READ(X[I])   END FOR   FOR K=1 TO N DO      PRINT("Generation";K;TAB(16);)      FOR J=1 TO W DO         IF X[J]=1 THEN PRINT("#";)  ELSE PRINT("_";) END IF         IF X[J-1]+X[J]+X[J+1]=2 THEN X2[J]=1 ELSE X2[J]=0 END IF      END FOR      PRINT      FOR J=1 TO W DO         X[J]=X2[J]      END FOR   END FOREND PROGRAM `
Output:
```Generation 1   _###_##_#_#_#_#__#__
Generation 2   _#_#####_#_#_#______
Generation 3   __##___##_#_#_______
Generation 4   __##___###_#________
Generation 5   __##___#_##_________
Generation 6   __##____###_________
Generation 7   __##____#_#_________
Generation 8   __##_____#__________
Generation 9   __##________________
Generation 10  __##________________
Generation 11  __##________________
Generation 12  __##________________
Generation 13  __##________________
Generation 14  __##________________
Generation 15  __##________________
Generation 16  __##________________
Generation 17  __##________________
Generation 18  __##________________
Generation 19  __##________________
Generation 20  __##________________
```

## Euphoria

`include machine.e function rules(integer tri)    return tri = 3 or tri = 5 or tri = 6end function function next_gen(atom gen)    atom new, bit    new = rules(and_bits(gen,3)*2) -- work with the first bit separately    bit = 2    while gen > 0 do        new += bit*rules(and_bits(gen,7))        gen = floor(gen/2) -- shift right        bit *= 2 -- shift left    end while    return newend function constant char_clear = '_', char_filled = '#' procedure print_gen(atom gen)    puts(1, int_to_bits(gen,32) * (char_filled - char_clear) + char_clear)    puts(1,'\n')end procedure function s_to_gen(sequence s)    s -= char_clear    return bits_to_int(s)end function atom gen, previnteger n n = 0prev = 0gen = bits_to_int(rand(repeat(2,32))-1)while gen != prev do    printf(1,"Generation %d: ",n)    print_gen(gen)    prev = gen    gen = next_gen(gen)    n += 1end while printf(1,"Generation %d: ",n)print_gen(gen)`
Output:
```Generation 0: ####__#_###_#_#_#_#_##___##_##__
Generation 1: ___#___##_##_#_#_#_###___#####__
Generation 2: _______######_#_#_##_#___#___#__
Generation 3: _______#____##_#_####___________
Generation 4: ____________###_##__#___________
Generation 5: ____________#_####______________
Generation 6: _____________##__#______________
Generation 7: _____________##_________________
Generation 8: _____________##_________________
```

## Factor

`USING: bit-arrays io kernel locals math sequences ;IN: cellular : bool-sum ( bool1 bool2 -- sum )    [ [ 2 ] [ 1 ] if ]    [ [ 1 ] [ 0 ] if ] if ;:: neighbours ( index world -- # )    index [ 1 - ] [ 1 + ] bi [ world ?nth ] [email protected] bool-sum ;: count-neighbours ( world -- neighbours )    [ length iota ] keep [ neighbours ] curry map ; : life-law ( alive? neighbours -- alive? )    swap [ 1 = ] [ 2 = ] if ;: step ( world -- world' )    dup count-neighbours [ life-law ] ?{ } 2map-as ;: print-cellular ( world -- )    [ CHAR: # CHAR: _ ? ] "" map-as print ;: main-cellular ( -- )    ?{ f t t t f t t f t f t f t f t f f t f f }    10 [ dup print-cellular step ] times print-cellular ;MAIN: main-cellular `
```( scratchpad ) "cellular" run
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________```

## Fantom

` class Automaton{  static Int[] evolve (Int[] array)  {    return array.map |Int x, Int i -> Int|    {      if (i == 0)         return ( (x + array[1] == 2) ? 1 : 0)      else if (i == array.size-1)        return ( (x + array[-2] == 2) ? 1 : 0)      else if (x + array[i-1] + array[i+1] == 2)        return 1      else        return 0          }  }   public static Void main ()   {    Int[] array := [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]    echo (array.join(""))    Int[] newArray := evolve(array)    while (newArray != array)    {      echo (newArray.join(""))      array = newArray      newArray = evolve(array)    }  }} `

## FOCAL

`1.1 S OLD(2)=1; S OLD(3)=1; S OLD(4)=1; S OLD(6)=1; S OLD(7)=11.2 S OLD(9)=1; S OLD(11)=1; S OLD(13)=1; S OLD(15)=1; S OLD(18)=11.3 F N=1,10; D 21.4 Q 2.1 F X=1,20; D 32.2 F X=1,20; D 62.3 F X=1,20; S OLD(X)=NEW(X)2.4 T ! 3.1 I (OLD(X-1)+OLD(X)+OLD(X+1)-2)4.1,5.1,4.1 4.1 S NEW(X)=0 5.1 S NEW(X)=1 6.1 I (-OLD(X))7.1,8.1,8.1 7.1 T "#" 8.1 T "."`
Output:
```.###.##.#.#.#.#..#..
.#.#####.#.#.#......
..##...##.#.#.......
..##...###.#........
..##...#.##.........
..##....###.........
..##....#.#.........
..##.....#..........
..##................
..##................
```

## Forth

`: init ( bits count -- )  0 do dup 1 and c, 2/ loop drop ; 20 constant sizecreate state \$2556e size init 0 c, : .state  cr size 0 do    state i + [email protected] if ." #" else space then  loop ; : ctable create does> + [email protected] ;ctable rules \$68 8 init : gen  state [email protected] ( window )  size 0 do    2*  state i + 1+ [email protected] or  7 and    dup rules state i + c!  loop drop ; : life1d ( n -- )  .state 1 do gen .state loop ; 10 life1d`

ouput

`  ### ## # # # #  #   # ##### # # #        ##   ## # #         ##   ### #          ##   # ##           ##    ###           ##    # #           ##     #            ##                  ##                 ok `

## Fortran

Works with: Fortran version 90 and later
`PROGRAM LIFE_1D   IMPLICIT NONE   LOGICAL :: cells(20) = (/ .FALSE., .TRUE., .TRUE., .TRUE., .FALSE., .TRUE., .TRUE., .FALSE., .TRUE., .FALSE., &                            .TRUE., .FALSE., .TRUE., .FALSE., .TRUE., .FALSE., .FALSE., .TRUE., .FALSE., .FALSE. /)  INTEGER :: i   DO i = 0, 9     WRITE(*, "(A,I0,A)", ADVANCE = "NO") "Generation ", i, ": "     CALL Drawgen(cells)     CALL Nextgen(cells)  END DO CONTAINS   SUBROUTINE Nextgen(cells)    LOGICAL, INTENT (IN OUT) :: cells(:)    LOGICAL :: left, centre, right    INTEGER :: i     left = .FALSE.    DO i = 1, SIZE(cells)-1       centre = cells(i)       right = cells(i+1)       IF (left .AND. right) THEN          cells(i) = .NOT. cells(i)       ELSE IF (.NOT. left .AND. .NOT. right) THEN          cells(i) = .FALSE.       END IF       left = centre    END DO    cells(SIZE(cells)) = left .AND. right  END SUBROUTINE Nextgen   SUBROUTINE Drawgen(cells)    LOGICAL, INTENT (IN OUT) :: cells(:)    INTEGER :: i     DO i = 1, SIZE(cells)       IF (cells(i)) THEN          WRITE(*, "(A)", ADVANCE = "NO") "#"       ELSE          WRITE(*, "(A)", ADVANCE = "NO") "_"       END IF    END DO    WRITE(*,*)  END SUBROUTINE Drawgen END PROGRAM LIFE_1D`
Output:
``` Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________```

## GFA Basic

` '' One Dimensional Cellular Automaton'start\$="01110110101010100100"max_cycles%=20 ! give a maximum depth'' Global variables hold the world, with two rows' world! is set up with 2 extra cells width, so there is a FALSE on either side' cur% gives the row for current world,' new% gives the row for the next world.'size%=LEN(start\$)DIM world!(size%+2,2)cur%=0new%=1clock%=0'@setup_world(start\$)OPENW 1CLEARW 1DO  @display_world  @update_world  EXIT IF @same_state  clock%=clock%+1  EXIT IF clock%>max_cycles% ! safety netLOOP~INP(2)CLOSEW 1'' parse given string to set up initial states in world' -- assumes world! is of correct size'PROCEDURE setup_world(defn\$)  LOCAL i%  ' clear out the array  ARRAYFILL world!(),FALSE  ' for each 1 in string, set cell to true  FOR i%=1 TO LEN(defn\$)    IF MID\$(defn\$,i%,1)="1"      world!(i%,0)=TRUE    ENDIF  NEXT i%  ' set references to cur and new  cur%=0  new%=1RETURN'' Display the world'PROCEDURE display_world  LOCAL i%  FOR i%=1 TO size%    IF world!(i%,cur%)      PRINT "#";    ELSE      PRINT ".";    ENDIF  NEXT i%  PRINT ""RETURN'' Create new version of world'PROCEDURE update_world  LOCAL i%  FOR i%=1 TO size%    world!(i%,new%)[email protected]_state(@get_value(i%))  NEXT i%  ' reverse cur/new  cur%=1-cur%  new%=1-new%RETURN'' Test if cur/new states are the same'FUNCTION same_state  LOCAL i%  FOR i%=1 TO size%    IF world!(i%,cur%)<>world!(i%,new%)      RETURN FALSE    ENDIF  NEXT i%  RETURN TRUEENDFUNC'' Return new state of cell given value'FUNCTION new_state(value%)  SELECT value%  CASE 0,1,2,4,7    RETURN FALSE  CASE 3,5,6    RETURN TRUE  ENDSELECTENDFUNC'' Compute value for cell + neighbours'FUNCTION get_value(cell%)  LOCAL result%  result%=0  IF world!(cell%-1,cur%)    result%=result%+4  ENDIF  IF world!(cell%,cur%)    result%=result%+2  ENDIF  IF world!(cell%+1,cur%)    result%=result%+1  ENDIF  RETURN result%ENDFUNC `

## Go

### Sequential

`package main import "fmt" const (    start    = "_###_##_#_#_#_#__#__"    offLeft  = '_'    offRight = '_'    dead     = '_') func main() {    fmt.Println(start)    g := newGenerator(start, offLeft, offRight, dead)    for i := 0; i < 10; i++ {        fmt.Println(g())    }} func newGenerator(start string, offLeft, offRight, dead byte) func() string {    g0 := string(offLeft) + start + string(offRight)    g1 := []byte(g0)    last := len(g0) - 1    return func() string {        for i := 1; i < last; i++ {            switch l := g0[i-1]; {            case l != g0[i+1]:                g1[i] = g0[i]            case g0[i] == dead:                g1[i] = l            default:                g1[i] = dead            }        }        g0 = string(g1)        return g0[1:last]    }}`
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________
```

### Concurrent

Computations run on each cell concurrently. Separate read and write phases. Single array of cells.

`package main import (    "fmt"    "sync") const (    start    = "_###_##_#_#_#_#__#__"    offLeft  = '_'    offRight = '_'    dead     = '_') func main() {    fmt.Println(start)    a := make([]byte, len(start)+2)    a[0] = offLeft    copy(a[1:], start)    a[len(a)-1] = offRight    var read, write sync.WaitGroup    read.Add(len(start) + 1)    for i := 1; i <= len(start); i++ {        go cell(a[i-1:i+2], &read, &write)    }    for i := 0; i < 10; i++ {        write.Add(len(start) + 1)        read.Done()        read.Wait()        read.Add(len(start) + 1)        write.Done()        write.Wait()        fmt.Println(string(a[1 : len(a)-1]))    }} func cell(kernel []byte, read, write *sync.WaitGroup) {    var next byte    for {        l, v, r := kernel[0], kernel[1], kernel[2]        read.Done()        switch {        case l != r:            next = v        case v == dead:            next = l        default:            next = dead        }        read.Wait()        kernel[1] = next        write.Done()        write.Wait()    }}`

Output is same as sequential version.

## Groovy

Solution:

`def life1D = { self ->    def right = self[1..-1] + [false]    def left = [false] + self[0..-2]    [left, self, right].transpose().collect { hood -> hood.count { it } == 2 }}`

Test:

`def cells = ('_###_##_#_#_#_#__#__' as List).collect { it == '#' }println "Generation 0: \${cells.collect { g -> g ? '#' : '_' }.join()}"(1..9).each {    cells = life1D(cells)    println "Generation \${it}: \${cells.collect { g -> g ? '#' : '_' }.join()}"}`
Output:
```Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________```

`import Data.List (unfoldr)import System.Random (newStdGen, randomRs) bnd :: String -> Charbnd "_##" = '#'bnd "#_#" = '#'bnd "##_" = '#'bnd _ = '_' nxt :: String -> Stringnxt = unfoldr go . ('_' :) . (<> "_")  where    go [_, _] = Nothing    go xs = Just (bnd \$ take 3 xs, drop 1 xs) lahmahgaan :: String -> [String]lahmahgaan xs =  init    . until      ((==) . last <*> last . init)      ((<>) <*> pure . nxt . last)    \$ [xs, nxt xs] main :: IO ()main =  newStdGen    >>= ( mapM_ putStrLn . lahmahgaan            . map ("_#" !!)            . take 36            . randomRs (0, 1)        )`
Output:

For example:

```_##_#_#__#_#_#_#_###_#######_#_#__##
_###_#____#_#_#_##_###_____##_#___##
_#_##______#_#_#####_#_____###____##
__###_______#_##___##______#_#____##
__#_#________###___##_______#_____##
___#_________#_#___##_____________##
______________#____##_____________##
___________________##_____________##```

## Icon and Unicon

` # One dimensional Cellular automatonrecord Automaton(size, cells) procedure make_automaton (size, items)  automaton := Automaton (size, items)  while (*items < size) do push (automaton.cells, 0)  return automatonend procedure automaton_display (automaton)  every (write ! automaton.cells)end procedure automaton_evolve (automaton)  revised := make_automaton (automaton.size, [])  # do the left-most cell  if ((automaton.cells[1] + automaton.cells[2]) = 2) then    revised.cells[1] := 1  # do the right-most cell  if ((automaton.cells[automaton.size] + automaton.cells[automaton.size-1]) = 2) then    revised.cells[revised.size] := 1  # do the intermediate cells  every (i := 2 to (automaton.size-1)) do {    if ((automaton.cells[i-1] + automaton.cells[i] + automaton.cells[i+1]) = 2) then      revised.cells[i] := 1  }  return revisedend procedure main ()  automaton := make_automaton (20, [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0])  every (1 to 10) do { # generations    automaton_display (automaton)    automaton := automaton_evolve (automaton)  }end `

An alternative approach is to represent the automaton as a string. The following solution takes advantage of the implicit type coercions between string and numeric values in Icon and Unicon. It also surrounds the automaton with a border of 'dead' (always 0) cells to eliminate the need to special case the first and last cells in the automaton. Although the main procedure displays up to the first 10 generations, the evolve procedure fails if a new generation is unchanged from the previous, stopping the generation cycle early.

`procedure main(A)  A := if *A = 0 then ["01110110101010100100"]  CA := show("0"||A[1]||"0")        # add always dead border cells  every CA := show(|evolve(CA)\10)  # limit to max of 10 generationsend procedure show(ca)  write(ca[2:-1])                   # omit border cells  return caend procedure evolve(CA)  newCA := repl("0",*CA)  every newCA[i := 2 to (*CA-1)] := (CA[i-1]+CA[i]+CA[i+1] = 2, "1")  return CA ~== newCA               # fail if no changeend`
A couple of sample runs:
```->odca
01110110101010100100
01011111010101000000
00110001101010000000
00110001110100000000
00110001011000000000
00110000111000000000
00110000101000000000
00110000010000000000
00110000000000000000
->odca 01110110
01110110
01011110
00110010
00110000
->```

## J

`life1d=: '_#'{~ (2 = 3+/\ 0,],0:)^:a:`
Example use:
`   life1d ? 20 # 2_###_##_#_#_#_#__#___#_#####_#_#_#________##___##_#_#_________##___###_#__________##___#_##___________##____###___________##____#_#___________##_____#____________##________________`

Alternative implementation:

`Rule=:2 :0 NB. , m: number of generations, n: rule number  '_#'{~ (3 ((|.n#:~8#2) {~ #.)\ 0,],0:)^:(i.m))`
Example use:
`   9 Rule 104 '#'='_###_##_#_#_#_#__#__'_###_##_#_#_#_#__#___#_#####_#_#_#________##___##_#_#_________##___###_#__________##___#_##___________##____###___________##____#_#___________##_____#____________##________________`

## Java

This example requires a starting generation of at least length two (which is what you need for anything interesting anyway).

`public class Life{	public static void main(String[] args) throws Exception{		String start= "_###_##_#_#_#_#__#__";		int numGens = 10;		for(int i= 0; i < numGens; i++){			System.out.println("Generation " + i + ": " + start);			start= life(start);		}	} 	public static String life(String lastGen){		String newGen= "";		for(int i= 0; i < lastGen.length(); i++){			int neighbors= 0;			if (i == 0){//left edge				neighbors= lastGen.charAt(1) == '#' ? 1 : 0;			} else if (i == lastGen.length() - 1){//right edge				neighbors= lastGen.charAt(i - 1) == '#' ? 1 : 0;			} else{//middle				neighbors= getNeighbors(lastGen.substring(i - 1, i + 2));			} 			if (neighbors == 0){//dies or stays dead with no neighbors				newGen+= "_";			}			if (neighbors == 1){//stays with one neighbor				newGen+= lastGen.charAt(i);			}			if (neighbors == 2){//flips with two neighbors				newGen+= lastGen.charAt(i) == '#' ? "_" : "#";			}		}		return newGen;	} 	public static int getNeighbors(String group){		int ans= 0;		if (group.charAt(0) == '#') ans++;		if (group.charAt(2) == '#') ans++;		return ans;	}}`
Output:
```Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________```
Translation of: C

In this version, `b` is replaced by a `backup` which is local to the `evolve` method, and the `evolve` method returns a boolean.

`public class Life{	private static char[] trans = "___#_##_".toCharArray(); 	private static int v(StringBuilder cell, int i){		return (cell.charAt(i) != '_') ? 1 : 0;	} 	public static boolean evolve(StringBuilder cell){		boolean diff = false;		StringBuilder backup = new StringBuilder(cell.toString()); 		for(int i = 1; i < cell.length() - 3; i++){			/* use left, self, right as binary number bits for table index */			backup.setCharAt(i, trans[v(cell, i - 1) * 4 + v(cell, i) * 2			      					+ v(cell, i + 1)]);			diff = diff || (backup.charAt(i) != cell.charAt(i));		} 		cell.delete(0, cell.length());//clear the buffer		cell.append(backup);//replace it with the new generation		return diff;	} 	public static void main(String[] args){		StringBuilder  c = new StringBuilder("_###_##_#_#_#_#__#__\n"); 		do{			System.out.printf(c.substring(1));		}while(evolve(c));	}}`
Output:
```###_##_#_#_#_#__#__
#_#####_#_#_#______
_##___##_#_#_______
_##___###_#________
_##___#_##_________
_##____###_________
_##____#_#_________
_##_____#__________
_##________________```

## JavaScript

The example below expects an array of 1s or 0s, as in the example. It also adds dead cells to both ends, which aren't included in the returned next generation.

state[i-1] refers to the new cell in question, (old[i] == 1) checks if the old cell was alive.

`function caStep(old) {  var old = [0].concat(old, [0]); // Surround with dead cells.  var state = []; // The new state.   for (var i=1; i<old.length-1; i++) {    switch (old[i-1] + old[i+1]) {      case 0: state[i-1] = 0; break;      case 1: state[i-1] = (old[i] == 1) ? 1 : 0; break;      case 2: state[i-1] = (old[i] == 1) ? 0 : 1; break;    }  }  return state;}`
Example usage:
`alert(caStep([0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]));`

## jq

The main point of interest in the following is perhaps the way the built-in function "recurse" is used to continue the simulation until quiescence.

`# The 1-d cellular automaton:def next:   # Conveniently, jq treats null as 0 when it comes to addition   # so there is no need to fiddle with the boundaries  . as \$old  | reduce range(0; length) as \$i    ([];     (\$old[\$i-1] + \$old[\$i+1]) as \$s     | if   \$s == 0 then .[\$i] = 0       elif \$s == 1 then .[\$i] = (if \$old[\$i] == 1 then 1 else 0 end)       else              .[\$i] = (if \$old[\$i] == 1 then 0 else 1 end)       end);  # pretty-print an array:def pp: reduce .[] as \$i (""; . + (if \$i == 0 then " " else "*" end)); # continue until quiescence:def go: recurse(. as \$prev | next | if . == \$prev then empty else . end) | pp; # Example:[0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0] | go`
Output:
`\$ jq -c -r -n -f One-dimensional_cellular_automata.jq *** ** * * * *  *   * ***** * * *        **   ** * *         **   *** *          **   * **           **    ***           **    * *           **     *            **`

## Julia

This solution creates an automaton with with either empty or periodic bounds. The empty bounds case, is typical of many of the solutions here. The periodic bounds case is a typical physics approach where, in effect, the beginning and end of the list touch each other to form a circular rather than linear array. In practice, the effects of boundary conditions are subtle for long arrays.

` function next_gen(a::BitArray{1}, isperiodic=false)    b = copy(a)    if isperiodic        ncnt = prepend!(a[1:end-1], [a[end]]) + append!(a[2:end], [a[1]])    else        ncnt = prepend!(a[1:end-1], [false]) + append!(a[2:end], [false])    end    b[ncnt .== 0] = false    b[ncnt .== 2] = ~b[ncnt .== 2]    return bend function show_gen(a::BitArray{1})    s = join([i ? "\u2588" : " " for i in a], "")    s = "\u25ba"*s*"\u25c4"end hi = 70a = bitrand(hi)b = falses(hi)println("A 1D Cellular Atomaton with ", hi, " cells and empty bounds.")while any(a) && any(a .!= b)    println("    ", show_gen(a))    b = copy(a)    a = next_gen(a)enda = bitrand(hi)b = falses(hi)println()println("A 1D Cellular Atomaton with ", hi, " cells and periodic bounds.")while any(a) && any(a .!= b)    println("    ", show_gen(a))    b = copy(a)    a = next_gen(a, true)end `
Output:
```A 1D Cellular Atomaton with 70 cells and empty bounds.
► ███  ██  █ ██   ███ █  ███  ██  █ █   ██████ █   ██ █ █ █  █ ██  ███ ◄
► █ █  ██   ███   █ ██   █ █  ██   █    █    ██    ███ █ █    ███  █ █ ◄
►  █   ██   █ █    ███    █   ██             ██    █ ██ █     █ █   █  ◄
►      ██    █     █ █        ██             ██     ████       █       ◄
►      ██           █         ██             ██     █  █               ◄
►      ██                     ██             ██                        ◄

A 1D Cellular Atomaton with 70 cells and periodic bounds.
►████   ██ █    █ █  ██  ██ █ █      ████   █    ███  ███ ██     ██ ██ ◄
►█  █   ███      █   ██  ███ █       █  █        █ █  █ ████     ██████◄
►█      █ █          ██  █ ██                     █    ██  █     █     ◄
►        █           ██   ███                          ██              ◄
►                    ██   █ █                          ██              ◄
►                    ██    █                           ██              ◄
►                    ██                                ██              ◄
```

## K

`f:{2=+/(0,x,0)@(!#x)+/:!3}`
Example usage:
`   `0:"_X"@f\0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0_XXX_XX_X_X_X_X__X___X_XXXXX_X_X_X________XX___XX_X_X_________XX___XXX_X__________XX___X_XX___________XX____XXX___________XX____X_X___________XX_____X____________XX________________ `

## Kotlin

Translation of: C
`// version 1.1.4-3 val trans = "___#_##_" fun v(cell: StringBuilder, i: Int) = if (cell[i] != '_') 1 else 0 fun evolve(cell: StringBuilder, backup: StringBuilder): Boolean {    val len = cell.length - 2    var diff = 0    for (i in 1 until len) {        /* use left, self, right as binary number bits for table index */        backup[i] = trans[v(cell, i - 1) * 4 + v(cell, i) * 2 + v(cell, i + 1)]        diff += if (backup[i] != cell[i]) 1 else 0    }    cell.setLength(0)    cell.append(backup)    return diff != 0} fun main(args: Array<String>) {    val c = StringBuilder("_###_##_#_#_#_#__#__")    val b = StringBuilder("____________________")    do {       println(c.substring(1))    }    while (evolve(c,b))}`
Output:
```###_##_#_#_#_#__#__
#_#####_#_#_#______
_##___##_#_#_______
_##___###_#________
_##___#_##_________
_##____###_________
_##____#_#_________
_##_____#__________
_##________________
```

## Liberty BASIC

Works with: Just BASIC
Works with: Run BASIC
`'   [RC] 'One-dimensional cellular automata' '    does not wrap so fails for some rulesrule\$ ="00010110"   '   Rule 22 decimal state\$ ="0011101101010101001000" for j =1 to 20    print state\$    oldState\$ =state\$    state\$ ="0"    for k =2 to len( oldState\$) -1        NHood\$ =mid\$( oldState\$, k -1, 3)  '   pick 3 char neighbourhood and turn binary string to decimal        vNHood =0        for kk =3 to 1 step -1            vNHood =vNHood +val( mid\$( NHood\$, kk, 1)) *2^( 3 -kk)        next kk                                        '  .... & use it to index into rule\$ to find appropriate new value        state\$ =state\$ +mid\$( rule\$, vNHood +1, 1)    next k    state\$ =state\$ +"0"  next j end`

## Locomotive Basic

`10 MODE 1:n=10:READ w:DIM x(w+1),x2(w+1):FOR i=1 to w:READ x(i):NEXT20 FOR k=1 TO n30 FOR j=1 TO w40 IF x(j) THEN PRINT "#"; ELSE PRINT "_";50 IF x(j-1)+x(j)+x(j+1)=2 THEN x2(j)=1 ELSE x2(j)=060 NEXT:PRINT70 FOR j=1 TO w:x(j)=x2(j):NEXT80 NEXT90 DATA 20,0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0`
Output:

## Logo

Works with: UCB Logo
`make "cell_list [0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0]make "generations 9 to evolve :nifelse :n=1 [make "nminus1 item :cell_count :cell_list][make "nminus1 item :n-1 :cell_list]ifelse :n=:cell_count[make "nplus1 item 1 :cell_list][make "nplus1 item :n+1 :cell_list]ifelse ((item :n :cell_list)=0) [	ifelse (and (:nminus1=1) (:nplus1=1)) [output 1][output (item :n :cell_list)]][	ifelse (and (:nminus1=1) (:nplus1=1)) [output 0][	   ifelse and (:nminus1=0) (:nplus1=0) [output 0][output (item :n :cell_list)]]]end to CA_1D :cell_list :generationsmake "cell_count count :cell_list(print ")make "printout "repeat :cell_count [make "printout word :printout ifelse (item repcount :cell_list)=1 ["#]["_]](print "Generation "0: :printout) repeat :generations [       (make "cell_list_temp [])       repeat :cell_count[             (make "cell_list_temp (lput (evolve repcount) :cell_list_temp))       ]       make "cell_list :cell_list_temp       make "printout "       repeat :cell_count [       	      make "printout word :printout ifelse (item repcount :cell_list)=1 ["#]["_]       ]       (print "Generation  word repcount ": :printout)]end CA_1D :cell_list :generations`
Output:
```Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________
```

## Lua

`num_iterations = 9f = { 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0 } function Output( f, l )    io.write( l, ":  " )    for i = 1, #f do        local c        if f[i] == 1 then c = '#' else c = '_' end        io.write( c )    end    print ""end Output( f, 0 ) for l = 1, num_iterations do    local g = {}    for i = 2, #f-1 do        if f[i-1] + f[i+1] == 1 then             g[i] = f[i]        elseif f[i] == 0 and f[i-1] + f[i+1] == 2 then            g[i] = 1        else            g[i] = 0         end    end    if f[1]  == 1 and f[2]    == 1 then g[1]  = 1 else g[1]  = 0 end    if f[#f] == 1 and f[#f-1] == 1 then g[#f] = 1 else g[#f] = 0 end            f, g = g, f     Output( f, l )end `
Output:
```0:  _###_##_#_#_#_#__#__
1:  _#_#####_#_#_#______
2:  __##___##_#_#_______
3:  __##___###_#________
4:  __##___#_##_________
5:  __##____###_________
6:  __##____#_#_________
7:  __##_____#__________
8:  __##________________
9:  __##________________```

## M4

`divert(-1)define(`set',`define(`\$1[\$2]',`\$3')')define(`get',`defn(`\$1[\$2]')')define(`setrange',`ifelse(`\$3',`',\$2,`define(\$1[\$2],\$3)`'setrange(\$1,   incr(\$2),shift(shift(shift([email protected]))))')') dnl  throw in sentinels at each end (0 and size+1) to make counting easydefine(`new',`set(\$1,size,eval(\$#-1))`'setrange(\$1,1,   shift([email protected]))`'set(\$1,0,0)`'set(\$1,\$#,0)') define(`for',   `ifelse(\$#,0,``\$0'',   `ifelse(eval(\$2<=\$3),1,   `pushdef(`\$1',\$2)\$4`'popdef(`\$1')\$0(`\$1',incr(\$2),\$3,`\$4')')')')define(`show',   `for(`k',1,get(\$1,size),`get(\$1,k) ')') dnl  swap(`a',a,`b')  using arg stack for tempdefine(`swap',`define(`\$1',\$3)`'define(`\$3',\$2)')define(`nalive',   `eval(get(\$1,decr(\$2))+get(\$1,incr(\$2)))')setrange(`live',0,0,1,0)setrange(`dead',0,0,0,1)define(`nv',   `ifelse(get(\$1,z),0,`get(dead,\$3)',`get(live,\$3)')')define(`evolve',   `for(`z',1,get(\$1,size),      `set(\$2,z,nv(\$1,z,nalive(\$1,z)))')')new(`a',0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0)set(`b',size,get(`a',size))`'set(`b',0,0)`'set(`b',incr(get(`a',size)),0)define(`x',`a')define(`y',`b')divertfor(`j',1,10,   `show(x)`'evolve(`x',`y')`'swap(`x',x,`y')')`'show(x)`
Output:
```0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0
0 1 0 1 1 1 1 1 0 1 0 1 0 1 0 0 0 0 0 0
0 0 1 1 0 0 0 1 1 0 1 0 1 0 0 0 0 0 0 0
0 0 1 1 0 0 0 1 1 1 0 1 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 1 0 1 1 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
```

## Mathematica / Wolfram Language

Built-in function:

`CellularAutomaton[{{0,0,_}->0,{0,1,0}->0,{0,1,1}->1,{1,0,0}->0,{1,0,1}->1,{1,1,0}->1,{1,1,1}->0},{{1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1},0},12]Print @@@ (% /. {1 -> "#", 0 -> "."});`

For succinctness, an integral rule can be used:

`CellularAutomaton[2^^01101000 (* == 104 *), {{1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1}, 0}, 12];`
Output:
`###.##.#.#.#.#..##.#####.#.#.#.....##...##.#.#......##...###.#.......##...#.##........##....###........##....#.#........##.....#.........##...............##...............##...............##...............##..............`

## MATLAB / Octave

`function one_dim_cell_automata(v,n)   V='_#';   while n>=0;	disp(V(v+1));	n = n-1;	v = filter([1,1,1],1,[0,v,0]);	v = v(3:end)==2;   end; end`
Output:
```octave:27> one_dim_cell_automata('01110110101010100100'=='1',20);
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________
...```

## Modula-3

Modula-3 provides a module `Word` for doing bitwise operations, but it segfaults when trying to use `BOOLEAN` types, so we use `INTEGER` instead.

`MODULE Cell EXPORTS Main; IMPORT IO, Fmt, Word; VAR culture := ARRAY [0..19] OF INTEGER {0, 1, 1, 1,                                          0, 1, 1, 0,                                          1, 0, 1, 0,                                          1, 0, 1, 0,                                          0, 1, 0, 0}; PROCEDURE Step(VAR culture: ARRAY OF INTEGER) =  VAR left: INTEGER := 0;      this, right: INTEGER;  BEGIN    FOR i := FIRST(culture) TO LAST(culture) - 1 DO      right := culture[i + 1];      this := culture[i];      culture[i] :=           Word.Or(Word.And(this, Word.Xor(left, right)), Word.And(Word.Not(this), Word.And(left, right)));      left := this;    END;    culture[LAST(culture)] := Word.And(culture[LAST(culture)], Word.Not(left));  END Step; PROCEDURE Put(VAR culture: ARRAY OF INTEGER) =  BEGIN    FOR i := FIRST(culture) TO LAST(culture) DO      IF culture[i] = 1 THEN        IO.PutChar('#');      ELSE        IO.PutChar('_');      END;    END;  END Put; BEGIN  FOR i := 0 TO 9 DO    IO.Put("Generation " & Fmt.Int(i) & " ");    Put(culture);    IO.Put("\n");    Step(culture);  END;END Cell.`
Output:
```Generation 0 _###_##_#_#_#_#__#__
Generation 1 _#_#####_#_#_#______
Generation 2 __##___##_#_#_______
Generation 3 __##___###_#________
Generation 4 __##___#_##_________
Generation 5 __##____###_________
Generation 6 __##____#_#_________
Generation 7 __##_____#__________
Generation 8 __##________________
Generation 9 __##________________
```

## MontiLang

`30 VAR length .35 VAR height .FOR length 0 ENDFOR 1 0 ARR VAR list . length 1 - VAR topLen . FOR topLen 0 ENDFOR 1 ARR VAR topLst .   DEF getNeighbors    1 - VAR tempIndex .     GET tempIndex SWAP     tempIndex 1 + VAR tempIndex .    GET tempIndex SWAP     tempIndex 1 + VAR tempIndex .    GET tempIndex SWAP .    FOR 3 TOSTR ROT ENDFOR    FOR 2 SWAP + ENDFOR  ENDDEF DEF printArr    LEN 1 - VAR stLen .    0 VAR j .    FOR stLen        GET j         TOSTR OUT .        j 1 + VAR j .    ENDFOR    || PRINT .ENDDEF FOR height    FOR length 0 ENDFOR ARR VAR next .    1 VAR i .    FOR length        list i getNeighbors VAR last .         i 1 - VAR ind .        last |111| ==         IF : .            next 0 INSERT ind        ENDIF         last |110| ==        IF : .            next 1 INSERT ind        ENDIF         last |101| ==        IF : .            next 1 INSERT ind        ENDIF         last |100| ==        IF : .            next 0 INSERT ind        ENDIF         last |011| ==        IF : .            next 1 INSERT ind        ENDIF         last |010| ==        IF : .            next 1 INSERT ind        ENDIF         last |001| ==        IF : .            next 1 INSERT ind        ENDIF         last |000| ==        IF : .            next 0 INSERT ind        ENDIF        clear        i 1 + VAR i .    ENDFOR     next printArr .    next 0 ADD APPEND . VAR list .ENDFOR`

## Nial

(life.nial)

`% we need a way to write a values and pass the same backwi is rest link [write, pass]% calculate the neighbors by rotating the array left and right and joining themneighbors is pack [pass, sum [-1 rotate,  1 rotate]]% calculate the individual birth and death of a single array elementigen is fork [ = [ + [first, second], 3 first], 0 first, = [ + [first, second], 2 first], 1 first, 0 first ]% apply that to the arraynextgen is each igen neighbors% 42life is fork [ > [sum pass, 0 first], life nextgen wi, pass ]`
Using it:
`|loaddefs 'life.nial'|I := [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]|life I`

## Nim

`import random  type  BoolArray  = array[30, bool]  Symbols    = array[bool, char]  proc neighbours(map: BoolArray, i: int): int =  if i > 0:             inc(result, int(map[i - 1]))  if i + 1 < len(map):  inc(result, int(map[i + 1])) proc print(map: BoolArray, symbols: Symbols) =  for i in map: write(stdout, symbols[i])  write(stdout, "\l") proc randomMap: BoolArray =  randomize()  for i in mitems(result): i = sample([true, false])  const  num_turns = 20  symbols   = ['_', '#']   T = true  F = false var map =   [F, T, T, T, F, T, T, F, T, F, T, F, T, F, T,    F, F, T, F, F, F, F, F, F, F, F, F, F, F, F] # map = randomMap()  # uncomment for random start print(map, symbols) for _ in 0 ..< num_turns:  var map2 = map   for i, v in pairs(map):    map2[i] =      if v: neighbours(map, i) == 1      else: neighbours(map, i) == 2   print(map2, symbols)   if map2 == map: break  map = map2`
Output:
```_###_##_#_#_#_#__#____________
_#_#####_#_#_#________________
__##___##_#_#_________________
__##___###_#__________________
__##___#_##___________________
__##____###___________________
__##____#_#___________________
__##_____#____________________
__##__________________________
__##__________________________```

Using a string character counting method:

`import strutils const  s_init: string = "_###_##_#_#_#_#__#__"  arrLen: int = 20 var q0: string = s_init & repeat('_',arrLen-20)var q1: string = q0 proc life(s:string): char =   var str: string = s   if len(normalize(str)) == 2:      # normalize eliminates underscores      return '#'   return '_' proc evolve(q: string): string =   result = repeat('_',arrLen)   #result[0] = '_'   for i in 1 .. q.len-1:      result[i] = life(substr(q & '_',i-1,i+1)) echo(q1)q1 = evolve(q0)echo(q1)while q1 != q0:   q0 = q1   q1 = evolve(q0)   echo(q1)`
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________```

Using nested functions and method calling style:

`proc cellAutomata =  proc evolveInto(x, t : var string) =    for i in x.low..x.high:      let        alive = x[i] == 'o'        left  = if i == x.low:  false else: x[i - 1] == 'o'        right = if i == x.high: false else: x[i + 1] == 'o'      t[i] =        if alive: (if left xor right: 'o' else: '.')        else:     (if left and right: 'o' else: '.')   var    x = ".ooo.oo.o.o.o.o..o.."    t = x   for i in 1..10:    x.echo    x.evolveInto t    swap t, x cellAutomata()`
Output:
```.ooo.oo.o.o.o.o..o..
.o.ooooo.o.o.o......
..oo...oo.o.o.......
..oo...ooo.o........
..oo...o.oo.........
..oo....ooo.........
..oo....o.o.........
..oo.....o..........
..oo................
..oo................```

## OCaml

`let get g i =  try g.(i)  with _ -> 0 let next_cell g i =  match get g (i-1), get g (i), get g (i+1) with  | 0, 0, 0 -> 0  | 0, 0, 1 -> 0  | 0, 1, 0 -> 0  | 0, 1, 1 -> 1  | 1, 0, 0 -> 0  | 1, 0, 1 -> 1  | 1, 1, 0 -> 1  | 1, 1, 1 -> 0  | _ -> assert(false) let next g =  let old_g = Array.copy g in  for i = 0 to pred(Array.length g) do    g.(i) <- (next_cell old_g i)  done let print_g g =  for i = 0 to pred(Array.length g) do    if g.(i) = 0    then print_char '_'    else print_char '#'  done;  print_newline()`

put the code above in a file named "life.ml", and then use it in the ocaml toplevel like this:

```#use "life.ml" ;;

let iter n g =
for i = 0 to n do
Printf.printf "Generation %d: " i; print_g g;
next g;
done
;;

let g_of_string str =
let f = (function '_' -> 0 | '#' -> 1 | _ -> assert false) in
Array.init (String.length str) (fun i -> f str.[i])
;;

# iter 9 (g_of_string "_###_##_#_#_#_#__#__") ;;
Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________
- : unit = ()
```

## Oforth

`: nextGen( l )| i s |   l byteSize dup ->s String newSize   s loop: i [       i 1 if=: [ 0 ] else: [ i 1- l byteAt '#' = ]      i l byteAt '#' = +       i s if=: [ 0 ] else: [ i 1+ l byteAt '#' = ] +       2 if=: [ '#' ] else: [ '_' ] over add      ]; : gen( l n -- )    l dup .cr #[ nextGen dup .cr ] times( n ) drop ;`
Output:
```"_###_##_#_#_#_#__#__" 10 gen
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________
ok
```

## Oz

`declare  A0 = {List.toTuple unit "_###_##_#_#_#_#__#__"}   MaxGenerations = 9   Rules = unit('___':&_               '__#':&_               '_#_':&_               '_##':&#               '#__':&_               '#_#':&#               '##_':&#               '###':&_)   fun {Evolve A}     {Record.mapInd A      fun {\$ I V}         Left = {CondSelect A I-1 &_}         Right = {CondSelect A I+1 &_}         Env = {String.toAtom [Left V Right]}      in         Rules.Env      end     }  end   fun lazy {Iterate X F}     X|{Iterate {F X} F}  endin  for     I in 0..MaxGenerations     A in {Iterate A0 Evolve}  do     {System.showInfo "Gen. "#I#": "#{Record.toList A}}  end`
Output:
```Gen. 0: _###_##_#_#_#_#__#__
Gen. 1: _#_#####_#_#_#______
Gen. 2: __##___##_#_#_______
Gen. 3: __##___###_#________
Gen. 4: __##___#_##_________
Gen. 5: __##____###_________
Gen. 6: __##____#_#_________
Gen. 7: __##_____#__________
Gen. 8: __##________________
Gen. 9: __##________________
```

## PARI/GP

This version defines the fixed cells to the left and right as dead; of course other versions are possible. This function generates one generation from a previous one, passed as a 0-1 vector.

`step(v)=my(u=vector(#v),k);u[1]=v[1]&v[2];u[#u]=v[#v]&v[#v-1];for(i=2,#v-1,k=v[i-1]+v[i+1];u[i]=if(v[i],k==1,k==2));u;`

To simulate a run of 10 generations of the automaton, the function above can be put in a loop that spawns a new generation as a function of nth generations passed (n=0 is the initial state):

`cur = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]; for(n=0, 9, print(cur); cur = step(cur));`

### Output

` [0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0][0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0][0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0][0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0][0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0][0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0][0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0][0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0][0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0][0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0] `

## Pascal

`program Test;{\$IFDEF FPC}{\$MODE DELPHI}{\$ELSE}{\$APPTYPE}{\$ENDIF}uses  sysutils;const  cCHAR: array[0..1] of char = ('_','#');type  TRow =  array of byte; function ConvertToRow(const s:string):tRow;var  i : NativeInt;Begin  i := length(s);  setlength(Result,length(s));  For i := i downto 0 do    result[i-1]:= ORD(s[i]=cChar[1]);end; function OutRow(const row:tRow):string;//create output stringvar  i: NativeInt;Begin  i := length(row);  setlength(result,i);  For i := i downto 1 do    result[i]:= cChar[row[i-1]];end; procedure NextRow(row:pByteArray;MaxIdx:NativeInt);//compute next row in place by the using a small storage for the //2 values, that would otherwise be overriddenvar  leftValue,Value: NativeInt;  i,trpCnt: NativeInt;Begin  leftValue := 0;  trpCnt := row[0]+row[1];   i := 0;  while i < MaxIdx do  Begin    Value := row[i];    //the rule for survive : PopCnt == 2    row[i] := ORD(trpCnt= 2);    //reduce popcnt of element before    dec(trpCnt,leftValue);    //goto next element    inc(i);    leftValue := Value;    //increment popcnt by right element    inc(trpCnt,row[i+1]);    //move to next position in ring buffer  end;  row[MaxIdx] := ORD(trpCnt= 2);end; const  TestString: string='  ### ## # # # #  #  ';var  s: string;  row:tRow;  i: NativeInt;begin  s := Teststring;  row:= ConvertToRow(s);  For i := 0 to 9 do  Begin    writeln(OutRow(row));    NextRow(@row[0],High(row));  end;end.`
Output:
```
__###_##_#_#_#_#__#__
__#_#####_#_#_#______
___##___##_#_#_______
___##___###_#________
___##___#_##_________
___##____###_________
___##____#_#_________
___##_____#__________
___##________________

___##________________```

## Perl

Use regexp to extract and substitute cells while the string changes

Convert cells to zeros and ones to set complement state

` \$_="_###_##_#_#_#_#__#__\n";do {  y/01/_#/;  print;  y/_#/01/;  s/(?<=(.))(.)(?=(.))/\$1 == \$3 ? \$1 ? 1-\$2 : 0 : \$2/eg;} while (\$x ne \$_ and \$x=\$_); `

Use hash for complement state

` \$_="_###_##_#_#_#_#__#__\n";%h=qw(# _ _ #);do {  print;  s/(?<=(.))(.)(?=(.))/\$1 eq \$3 ? \$1 eq "_" ? "_" : \$h{\$2} : \$2/eg;} while (\$x ne \$_ and \$x=\$_); `
Output:
for both versions:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________```

## Phix

Ludicrously optimised:

```string s = "_###_##_#_#_#_#__#__"
integer prev='_', curr, toggled = 1

while 1 do
?s
for i=2 to length(s)-1 do
curr = s[i]
if prev=s[i+1]
and (curr='#' or prev='#') then
s[i] = 130-curr
toggled = 1
end if
prev = curr
end for
if not toggled then ?s exit end if
toggled = 0
end while
```
Output:
```"_###_##_#_#_#_#__#__"
"_#_#####_#_#_#______"
"__##___##_#_#_______"
"__##___###_#________"
"__##___#_##_________"
"__##____###_________"
"__##____#_#_________"
"__##_____#__________"
"__##________________"
"__##________________"
```

And of course I had to have a crack at that Sierpinski_Triangle:

```string s = "________________________#________________________"
integer prev='_', curr, toggled = 1

for limit=1 to 24 do
?s
for i=2 to length(s)-1 do
curr = s[i]
if (prev=s[i+1]) = (curr='#') then
s[i] = 130-curr
end if
prev = curr
end for
end for
```
Output:
```"________________________#________________________"
"_______________________#_#_______________________"
"______________________#___#______________________"
"_____________________#_#_#_#_____________________"
"____________________#_______#____________________"
"___________________#_#_____#_#___________________"
"__________________#___#___#___#__________________"
"_________________#_#_#_#_#_#_#_#_________________"
"________________#_______________#________________"
"_______________#_#_____________#_#_______________"
"______________#___#___________#___#______________"
"_____________#_#_#_#_________#_#_#_#_____________"
"____________#_______#_______#_______#____________"
"___________#_#_____#_#_____#_#_____#_#___________"
"__________#___#___#___#___#___#___#___#__________"
"_________#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_#_________"
"________#_______________________________#________"
"_______#_#_____________________________#_#_______"
"______#___#___________________________#___#______"
"_____#_#_#_#_________________________#_#_#_#_____"
"____#_______#_______________________#_______#____"
"___#_#_____#_#_____________________#_#_____#_#___"
"__#___#___#___#___________________#___#___#___#__"
"_#_#_#_#_#_#_#_#_________________#_#_#_#_#_#_#_#_"
```

## Phixmonti

`0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0 stklen var ww tolist 0 0 put0 w 1 + repeat var x2 10 for	drop	w for		var j		j get 1 == if "#" else "_" endif print		j 1 - get var p1 j get swap j 1 + get rot p1 + + 2 ==		x2 swap j set var x2	endfor	nl	drop x2endfor`

## Picat

`go =>   %    _ # # # _ # # _ # _ # _ # _ # _ _ # _ _   S = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0],   println(init=S),   run_ca(S),   nl,    println("Some random inits:"),   _ = random2(),   foreach(N in [5,10,20,50])     S2 = [random() mod 2 : _I in 1..N],     run_ca(S2),     nl    end. %% Run a CA and show the result.% % rule/1 is the defaultrun_ca(S) =>  run_ca(S,rule).run_ca(S,Rules) =>  Len = S.length,  All := [S],  Seen = new_map(), % detect fixpoint and cycle  while (not Seen.has_key(S))    Seen.put(S,1),    T = [S[1]] ++ [apply(Rules, slice(S,I-1,I+1)) : I in 2..Len-1] ++ [S[Len]],    All := All ++ [T],    S := T  end,  foreach(A in All) println(A.convert()) end,  writeln(len=All.length). % Convert:%  0->"_"%  1->"#"convert(L) = Res =>    B = "_#",    Res = [B[L[I]+1] : I in 1..L.length]. % the rulesrule([0,0,0]) = 0. % rule([0,0,1]) = 0. %rule([0,1,0]) = 0. % Dies without enough neighboursrule([0,1,1]) = 1. % Needs one neighbour to surviverule([1,0,0]) = 0. %rule([1,0,1]) = 1. % Two neighbours giving birthrule([1,1,0]) = 1. % Needs one neighbour to surviverule([1,1,1]) = 0. % Starved to death.`
Output:
```init = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
len = 10

Some random inits:
_###_
_#_#_
__#__
_____
_____
len = 5

_#___##_#_
_____###__
_____#_#__
______#___
__________
__________
len = 6

###__####_#___#___##
#_#__#__##________##
##______##________##
##______##________##
len = 4

______###_#_#___####__#_______#__#___#_####__#_###
______#_##_#____#__#__________________##__#___##_#
_______####___________________________##______####
_______#__#___________________________##______#__#
______________________________________##_________#
______________________________________##_________#
len = 6```

The program is fairly general. Here's the additional code for the rule 30 CA.

`go2 =>    N = 4,   Ns = [0 : _ in 1..N],   S = Ns ++ [1] ++ Ns,   run_ca(S, rule30). % The rules for rule 30rule30([0,0,0]) = 0.rule30([0,0,1]) = 1.rule30([0,1,0]) = 1.rule30([0,1,1]) = 1.rule30([1,0,0]) = 1.rule30([1,0,1]) = 0.rule30([1,1,0]) = 0.rule30([1,1,1]) = 0.`

## PicoLisp

`(let Cells (chop "_###_##_#_#_#_#__#__")   (do 10      (prinl Cells)      (setq Cells         (make            (link "_")            (map               '((L)                  (case (head 3 L)                     (`(mapcar chop '("___" "__#" "_#_" "#__" "###"))                         (link "_") )                     (`(mapcar chop '("_##" "#_#" "##_"))                        (link "#") ) ) )               Cells )            (link "_") ) ) ) )`
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________```

## Prolog

Works ith SWI-Prolog.

`one_dimensional_cellular_automata(L) :-	maplist(my_write, L), nl,	length(L, N),	length(LN, N),	% there is a 0 before the beginning	compute_next([0 |L], LN),	(   L \= LN -> one_dimensional_cellular_automata(LN); true). % All the possibilitescompute_next([0, 0, 0 | R], [0 | R1]) :-	compute_next([0, 0 | R], R1). compute_next([0, 0, 1 | R], [0 | R1]) :-	compute_next([0, 1 | R], R1). compute_next([0, 1, 0 | R], [0 | R1]) :-	compute_next([1, 0 | R], R1). compute_next([0, 1, 1 | R], [1 | R1]) :-	compute_next([1, 1 | R], R1). compute_next([1, 0, 0 | R], [0 | R1]) :-	compute_next([0, 0 | R], R1). compute_next([1, 0, 1 | R], [1 | R1]) :-	compute_next([0, 1 | R], R1). compute_next([1, 1, 0 | R], [1 | R1]) :-	compute_next([1, 0 | R], R1). compute_next([1, 1, 1 | R], [0 | R1]) :-	compute_next([1, 1 | R], R1). % the last four possibilies =>% we consider that there is à 0  after the endcomplang jq># The 1-d cellular automaton:def next:   # Conveniently, jq treats null as 0 when it comes to addition   # so there is no need to fiddle with the boundaries  . as \$old  | reduce range(0; length) as \$i    ([];     (\$old[\$i-1] + \$old[\$i+1]) as \$s     | if   \$s == 0 then .[\$i] = 0       elif \$s == 1 then .[\$i] = (if \$old[\$i] == 1 then 1 else 0 end)       else              .[\$i] = (if \$old[\$i] == 1 then 0 else 1 end)       end);  # pretty-print an array:def pp: reduce .[] as \$i (""; . + (if \$i == 0 then " " else "*" end)); # continue until quiescence:def go: recurse(. as \$prev | next | if . == \$prev then empty else . end) | pp; # Example:[0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0] | goute_next([0, 0], [0]). compute_next([1, 0], [0]). compute_next([0, 1], [0]). compute_next([1, 1], [1]). my_write(0) :-	write(.). my_write(1) :-	write(#). one_dimensional_cellular_automata :-	L = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0],	one_dimensional_cellular_automata(L). `
Output:
``` ?- one_dimensional_cellular_automata.
.###.##.#.#.#.#..#..
.#.#####.#.#.#......
..##...##.#.#.......
..##...###.#........
..##...#.##.........
..##....###.........
..##....#.#.........
..##.....#..........
..##................
true .
```

## PureBasic

`EnableExplicitDim cG.i(21) Dim nG.i(21)Define.i n, Gen DataSection  Data.i 0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0EndDataSectionFor n=1 To 20  Read.i cG(n)Next OpenConsole()Repeat  Print("Generation "+Str(Gen)+": ")  For n=1 To 20    Print(Chr(95-cG(n)*60))  Next  Gen +1  PrintN("")  For n=1 To 20    If (cG(n) And (cG(n-1) XOr cg(n+1))) Or (Not cG(n) And (cG(n-1) And cg(n+1)))     nG(n)=1   Else     nG(n)=0      EndIf      Next   CopyArray(nG(), cG())Until Gen > 9 PrintN("Press any key to exit"): Repeat: Until Inkey() <> ""`
Output:
```Generation 0: _###_##_#_#_#_#__#__
Generation 1: _#_#####_#_#_#______
Generation 2: __##___##_#_#_______
Generation 3: __##___###_#________
Generation 4: __##___#_##_________
Generation 5: __##____###_________
Generation 6: __##____#_#_________
Generation 7: __##_____#__________
Generation 8: __##________________
Generation 9: __##________________```

## Python

### Procedural

#### Python: Straightforward interpretation of spec

`import random printdead, printlive = '_#'maxgenerations = 10cellcount = 20offendvalue = '0' universe = ''.join(random.choice('01') for i in range(cellcount)) neighbours2newstate = { '000': '0', '001': '0', '010': '0', '011': '1', '100': '0', '101': '1', '110': '1', '111': '0', } for i in range(maxgenerations):    print "Generation %3i:  %s" % ( i,          universe.replace('0', printdead).replace('1', printlive) )    universe = offendvalue + universe + offendvalue    universe = ''.join(neighbours2newstate[universe[i:i+3]] for i in range(cellcount))`
Output:
```Generation   0:  _###_##_#_#_#_#__#__
Generation   1:  _#_#####_#_#_#______
Generation   2:  __##___##_#_#_______
Generation   3:  __##___###_#________
Generation   4:  __##___#_##_________
Generation   5:  __##____###_________
Generation   6:  __##____#_#_________
Generation   7:  __##_____#__________
Generation   8:  __##________________
Generation   9:  __##________________```

#### Python: Using boolean operators on bits

The following implementation uses boolean operations to realize the function.

`import random nquads = 5maxgenerations = 10fmt = '%%0%ix'%nquadsnbits = 4*nquadsa = random.getrandbits(nbits)  << 1#a = int('01110110101010100100', 2) << 1endmask = (2<<nbits)-2;endvals = 0<<(nbits+1) | 0tr = ('____', '___#', '__#_', '__##', '_#__', '_#_#', '_##_', '_###',      '#___', '#__#', '#_#_', '#_##', '##__', '##_#', '###_', '####' )for i in range(maxgenerations):   print "Generation %3i:  %s" % (i,(''.join(tr[int(t,16)] for t in (fmt%(a>>1)))))   a |= endvals   a = ((a&((a<<1) | (a>>1))) ^ ((a<<1)&(a>>1))) & endmask`

#### Python: Sum neighbours == 2

This example makes use of the observation that a cell is alive in the next generation if the sum with its current neighbours of alive cells is two.

`>>> gen = [ch == '#' for ch in '_###_##_#_#_#_#__#__']>>> for n in range(10):	print(''.join('#' if cell else '_' for cell in gen))	gen = [0] + gen + [0]	gen = [sum(gen[m:m+3]) == 2 for m in range(len(gen)-2)]  _###_##_#_#_#_#__#___#_#####_#_#_#________##___##_#_#_________##___###_#__________##___#_##___________##____###___________##____#_#___________##_____#____________##__________________##________________>>> `

### Composition of pure functions

Interpreting the rule shown in the task description as Wolfram rule 104, and generalising enough to allow for other rules of this kind:

`'''Cellular Automata''' from itertools import islice, repeatfrom functools import reducefrom random import randint  # nextRowByRule :: Int -> [Bool] -> [Bool]def nextRowByRule(intRule):    '''A row of booleans derived by Wolfram rule n       from another boolean row of the same length.    '''    # step :: (Bool, Bool, Bool) -> Bool    def step(l, x, r):        return bool(intRule & 2**intFromBools([l, x, r]))     # go :: [Bool] -> [Bool]    def go(xs):        return [False] + list(map(            step,            xs, xs[1:], xs[2:]        )) + [False]    return go  # intFromBools :: [Bool] -> Intdef intFromBools(xs):    '''Integer derived by binary interpretation       of a list of booleans.    '''    def go(b, pn):        power, n = pn        return (2 * power, n + power if b else n)    return foldr(go)([1, 0])(xs)[1]  # ------------------------- TEST -------------------------# main :: IO ()def main():    '''Samples of Wolfram rule evolutions.    '''    print(        unlines(map(showRuleSample, [104, 30, 110]))    )  # ----------------------- DISPLAY ------------------------ # showRuleSample :: Int -> Stringdef showRuleSample(intRule):    '''16 steps in the evolution       of a given Wolfram rule.    '''    return 'Rule ' + str(intRule) + ':\n' + (        unlines(map(            showCells,            take(16)(                iterate(nextRowByRule(intRule))(                    onePixelInLineOf(64) if (                        bool(randint(0, 1))                    ) else randomPixelsInLineOf(64)                )            )        ))    )  # boolsFromInt :: Int -> [Bool]def boolsFromInt(n):    '''List of booleans derived by binary       decomposition of an integer.    '''    def go(x):        return Just((x // 2, bool(x % 2))) if x else Nothing()    return unfoldl(go)(n)  # nBoolsFromInt :: Int -> Int -> [Bool]def nBoolsFromInt(n):    '''List of bools, left-padded to given length n,       derived by binary decomposition of an integer x.    '''    def go(n, x):        bs = boolsFromInt(x)        return list(repeat(False, n - len(bs))) + bs    return lambda x: go(n, x)  # onePixelInLineOf :: Int -> [Bool]def onePixelInLineOf(n):    '''A row of n (mainly False) booleans,       with a single True value in the middle.    '''    return nBoolsFromInt(n)(        2**(n // 2)    )  # randomPixelsInLineOf :: Int -> [Bool]def randomPixelsInLineOf(n):    '''A row of n booleans with pseudorandom values.    '''    return [bool(randint(0, 1)) for _ in range(1, 1 + n)]  # showCells :: [Bool] -> Stringdef showCells(xs):    '''A block string representation of a list of booleans.    '''    return ''.join([chr(9608) if x else ' ' for x in xs])  # ----------------------- GENERIC ------------------------ # Just :: a -> Maybe adef Just(x):    '''Constructor for an inhabited Maybe (option type) value.       Wrapper containing the result of a computation.    '''    return {'type': 'Maybe', 'Nothing': False, 'Just': x}  # Nothing :: () -> Maybe adef Nothing():    '''Constructor for an empty Maybe (option type) value.       Empty wrapper returned where a computation is not possible.    '''    return {'type': 'Maybe', 'Nothing': True}  # foldr :: (a -> b -> b) -> b -> [a] -> bdef foldr(f):    '''Right to left reduction of a list,       using the binary operator f, and       starting with an initial accumulator value.    '''    def g(a, x):        return f(x, a)    return lambda acc: lambda xs: reduce(        g, xs[::-1], acc    )  # iterate :: (a -> a) -> a -> Gen [a]def iterate(f):    '''An infinite list of repeated       applications of f to x.    '''    def go(x):        v = x        while True:            yield v            v = f(v)    return go  # take :: Int -> [a] -> [a]# take :: Int -> String -> Stringdef take(n):    '''The prefix of xs of length n,       or xs itself if n > length xs.    '''    def go(xs):        return (            xs[0:n]            if isinstance(xs, (list, tuple))            else list(islice(xs, n))        )    return go  # unfoldl :: (b -> Maybe (b, a)) -> b -> [a]def unfoldl(f):    '''Dual to reduce or foldl.       Where these reduce a list to a summary value, unfoldl       builds a list from a seed value.       Where f returns Just(a, b), a is appended to the list,       and the residual b is used as the argument for the next       application of f.       When f returns Nothing, the completed list is returned.    '''    def go(v):        x, r = v, v        xs = []        while True:            mb = f(x)            if mb.get('Nothing'):                return xs            else:                x, r = mb.get('Just')                xs.insert(0, r)        return xs    return go  # unlines :: [String] -> Stringdef unlines(xs):    '''A single string formed by the intercalation       of a list of strings with the newline character.    '''    return '\n'.join(xs)  # MAIN -------------------------------------------------if __name__ == '__main__':    main()`
Output:
```Rule 104:
█  █  ████  ██    █   █      █ █ █ ██    █████ ██  ██  █ ██
█  █  ██                █ █ ███    █   ████  ██   ███
██                 █ ██ █        █  █  ██   █ █
██                  ████               ██    █
██                  █  █               ██
██                                     ██
██                                     ██
██                                     ██
██                                     ██
██                                     ██
██                                     ██
██                                     ██
██                                     ██
██                                     ██
██                                     ██
██                                     ██
Rule 30:
█
███
██  █
██ ████
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██ ████ ██  ███ ███  ██ ███
██  █    █ ███   █  ███  █  █
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Rule 110:
█  █  ██ ██  ██  █ █  ██  ███ █ █ ███     ██ ██    █    █   █
██ ██████ ███ ████ ███ ██ ███████ █    ██████   ██   ██  ██
█████    ███ ███  ███ ██████     ███   ██    █  ███  ███ ███
█   █   ██ ███ █ ██ ███    █    ██ █  ███   ██ ██ █ ██ ███ █
█  ██  █████ ████████ █   ██   █████ ██ █  █████████████ ███
█ ███ ██   ███      ███  ███  ██   ██████ ██           ███ █
███ ████  ██ █     ██ █ ██ █ ███  ██    ████          ██ ███
█ ███  █ █████    ████████████ █ ███   ██  █         █████ █
███ █ ████   █   ██          █████ █  ███ ██        ██   ███
█ █████  █  ██  ███         ██   ███ ██ ████       ███  ██ █
███   █ ██ ███ ██ █        ███  ██ ██████  █      ██ █ █████
█ █  ███████ ██████       ██ █ █████    █ ██     ███████   █
███ ██     ███    █      ███████   █   █████    ██     █  ██
█ ████    ██ █   ██     ██     █  ██  ██   █   ███    ██ ███
███  █   █████  ███    ███    ██ ███ ███  ██  ██ █   █████ █
█ █ ██  ██   █ ██ █   ██ █   █████ ███ █ ███ █████  ██   ███   ```

## Quackery

` [ stack 0 ]                     is cells    (   --> s )  [ dup size cells replace   0 swap witheach      [ char # =        | 1 << ] ]                is setup    ( \$ --> n )  [ 0 swap    cells share times      [ dup i >> 7 &        [ table 0 0 0 1 0 1 1 0 ]       rot 1 << | swap ]    drop 1 << ]                   is nextline ( n --> n )   [ cells share times      [ dup i 1+ bit &         iff [ char # ]        else [ char _ ]         emit ]     cr drop ]                    is echoline ( n -->   )   [ setup    [ dup echoline       dup nextline       tuck = until ]    echoline ]                   is automate ( \$ -->   )   \$ "_###_##_#_#_#_#__#__" automate`
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
```

## R

`set.seed(15797, kind="Mersenne-Twister") maxgenerations = 10cellcount = 20offendvalue = FALSE ## Cells are alive if TRUE, dead if FALSEuniverse <- c(offendvalue,              sample( c(TRUE, FALSE), cellcount, replace=TRUE),              offendvalue) ## List of patterns in which the cell stays alivestayingAlive <- lapply(list(c(1,1,0),                            c(1,0,1),                            c(0,1,0)), as.logical) ## x : length 3 logical vector## map: list of length 3 logical vectors that map to patterns##      in which x stays alivedeadOrAlive <- function(x, map) list(x) %in% map cellularAutomata <- function(x, map) {    c(x[1], apply(embed(x, 3), 1, deadOrAlive, map=map), x[length(x)])} deadOrAlive2string <- function(x) {    paste(ifelse(x, '#', '_'), collapse="")} for (i in 1:maxgenerations) {    universe <- cellularAutomata(universe, stayingAlive)    cat(format(i, width=3), deadOrAlive2string(universe), "\n")}`
Output:
```  1 _##_____####_#___#_#__
2 _##_____#__##_____#___
3 _##________##_________
4 _##________##_________
5 _##________##_________
6 _##________##_________
7 _##________##_________
8 _##________##_________
9 _##________##_________
10 _##________##_________
```

## Racket

`#lang racket (define (update cells)  (for/list ([crowding (map +                            (append '(0) (drop-right cells 1))                            cells                            (append (drop cells 1) '(0)))])    (if (= 2 crowding) 1 0))) (define (life-of cells time)  (unless (zero? time)    (displayln cells)    (life-of (update cells) (sub1 time)))) (life-of '(0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0)         10) #| (0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0)   (0 1 0 1 1 1 1 1 0 1 0 1 0 1 0 0 0 0 0 0)   (0 0 1 1 0 0 0 1 1 0 1 0 1 0 0 0 0 0 0 0)   (0 0 1 1 0 0 0 1 1 1 0 1 0 0 0 0 0 0 0 0)   (0 0 1 1 0 0 0 1 0 1 1 0 0 0 0 0 0 0 0 0)   (0 0 1 1 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0)   (0 0 1 1 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0)   (0 0 1 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0)   (0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0)   (0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0) |#`

Below is an alternative implementation using graphical output in the Racket REPL. It works with DrRacket and Emacs + Geiser.

`#lang slideshow ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; Simulation of cellular automata, as described by Stephen Wolfram in his 1983 paper.;; Uses Racket's inline image display capability for visual presentation	 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; (require racket/draw)(require slideshow) (define *rules* '((1 1 1) (1 1 0) (1 0 1) (1 0 0)		  (0 1 1) (0 1 0) (0 0 1) (0 0 0))) (define (bordered-square n)  (filled-rectangle n n #:draw-border? #t)) (define (draw-row lst)  (apply hc-append 2 (map (λ (x) (colorize (bordered-square 10) (cond ((= x 0) "gray")								      ((= x 1) "red")								      (else "gray"))))			  lst))) (define (extract-neighborhood nth prev-row)  (take (drop (append '(0) prev-row '(0)) nth) 3)) (define (automaton-to-bits n)  (reverse (map (λ (y) (if (zero? (bitwise-and y n)) 0 1)) 		(map (λ (x) (expt 2 x)) (range 0 8))))) (define (get-rules bits)  (map cdr (filter (λ (x) (= (car x) 1)) (map cons bits *rules*)))) (define (advance-row old-row rules)  (let ([new '()])    (for ([i (in-range 0 (length old-row))])      (set! new (cons (if (member (extract-neighborhood i old-row)				  rules) 1 0) new)))    (reverse new))) (define (draw-automaton automaton init-row row-number)  (let* ([bit-representation (automaton-to-bits automaton)]	 [rules (get-rules bit-representation)]	 [rows (list init-row)])    (for ([i (in-range 1 row-number)])      (set! rows (cons (advance-row (car rows) rules)		       rows)))    (apply vc-append 2 (map draw-row (reverse rows))))) (draw-automaton 104 '(0 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0 0) 10)`

## Raku

(formerly Perl 6)

Works with: rakudo version 2014-02-27

We'll make a general algorithm capable of computing any cellular automata as defined by Stephen Wolfram's famous book A new kind of Science. We will take the liberty of wrapping the array of cells as it does not affect the result much and it makes the implementation a lot easier.

`class Automaton {    has \$.rule;    has @.cells;    has @.code = \$!rule.fmt('%08b').flip.comb».Int;     method gist { "|{ @!cells.map({+\$_ ?? '#' !! ' '}).join }|" }     method succ {        self.new: :\$!rule, :@!code, :cells(             @!code[                    4 «*« @!cells.rotate(-1)                »+« 2 «*« @!cells                »+«       @!cells.rotate(1)            ]        )    }} #  The rule proposed for this task is rule 0b01101000 = 104 my @padding = 0 xx 5;my Automaton \$a .= new:    rule  => 104,    cells => flat @padding, '111011010101'.comb, @padding;say \$a++ for ^10;  # Rule 104 is not particularly interesting so here is [[wp:Rule 90|Rule 90]], # which shows a [[wp:Sierpinski Triangle|Sierpinski Triangle]]. say '';@padding = 0 xx 25;\$a = Automaton.new: :rule(90), :cells(flat @padding, 1, @padding); say \$a++ for ^20;`
Output:
```|     ### ## # # #     |
|     # ##### # #      |
|      ##   ## #       |
|      ##   ###        |
|      ##   # #        |
|      ##    #         |
|      ##              |
|      ##              |
|      ##              |
|      ##              |

|                         #                         |
|                        # #                        |
|                       #   #                       |
|                      # # # #                      |
|                     #       #                     |
|                    # #     # #                    |
|                   #   #   #   #                   |
|                  # # # # # # # #                  |
|                 #               #                 |
|                # #             # #                |
|               #   #           #   #               |
|              # # # #         # # # #              |
|             #       #       #       #             |
|            # #     # #     # #     # #            |
|           #   #   #   #   #   #   #   #           |
|          # # # # # # # # # # # # # # # #          |
|         #                               #         |
|        # #                             # #        |
|       #   #                           #   #       |
|      # # # #                         # # # #      |
```

## Red

`Red [    Purpose: "One-dimensional cellular automata"    Author: "Joe Smith"] vals: [0 1 0]kill: [[0 0] [#[none] 0] [0 #[none]]]evo: function [petri] [	new-petri: copy petri	while [petri/1] [		if all [petri/-1 = 1 petri/2 = 1] [new-petri/1: select vals petri/1]		if find/only kill reduce [petri/-1 petri/2] [new-petri/1: 0]		petri: next petri new-petri: next new-petri 	]	petri: head petri new-petri: head new-petri	clear insert petri new-petri] display: function [petri] [	print replace/all (replace/all to-string petri "0" "_") "1" "#"	petri	 ] loop 10 [	evo display [1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0]] `
Output:
```###_##_#_#_#_#__#_
#_#####_#_#_#_____
_##___##_#_#______
_##___###_#_______
_##___#_##________
_##____###________
_##____#_#________
_##_____#_________
_##_______________
_##_______________
```

## Retro

`# 1D Cellular Automota Assume an array of cells with an initial distribution of live anddead cells, and imaginary cells off the end of the array havingfixed values. Cells in the next generation of the array are calculated based onthe value of the cell and its left and right nearest neighbors inthe current generation. If, in the following table, a live cell is represented by 1 and adead cell by 0 then to generate the value of the cell at a particularindex in the array of cellular values you use the following table: 000 -> 0  # 001 -> 0  #010 -> 0  # Dies without enough neighbours011 -> 1  # Needs one neighbour to survive100 -> 0  #101 -> 1  # Two neighbours giving birth110 -> 1  # Needs one neighbour to survive111 -> 0  # Starved to death. I had originally written an implementation of this in RETRO 11.For RETRO 12 I took advantage of new language features and somefurther considerations into the rules for this task. The first word, `string,` inlines a string to `here`. I'll usethis to setup the initial input. ~~~:string, (s-) [ , ] s:for-each #0 , ; ~~~ The next two lines setup an initial generation and a buffer forthe evolved generation. In this case, `This` is the current generation and `Next` reflects the next step in the evolution. ~~~'This d:create   '.###.##.#.#.#.#..#.. string,  'Next d:create   '.................... string, ~~~ I use `display` to show the current generation. ~~~:display (-)   &This s:put nl ; ~~~ As might be expected, `update` copies the `Next` generation tothe `This` generation, setting things up for the next cycle. ~~~:update (-)   &Next &This dup s:length copy ; ~~~ The word `group` extracts a group of three cells. This data willbe passed to `evolve` for processing. ~~~:group (a-nnn)   [ fetch ]   [ n:inc fetch ]   [ n:inc n:inc fetch ] tri ; ~~~ I use `evolve` to decide how a cell should change, based on itsinitial state with relation to its neighbors. In the prior implementation this part was much more complex as I tallied things up and had separate conditions for each combination. This time I take advantage of the fact that only cells with two neighbors will be alive in the next generation. So the process is: - take the data from `group`- compare to `\$#` (for living cells)- add the flags- if the result is `#-2`, the cell should live- otherwise it'll be dead ~~~:evolve (nnn-c)   [ \$# eq? ] [email protected] + +   #-2 eq? [ \$# ] [ \$. ] choose ; ~~~ For readability I separated out the next few things. `at` takes anindex and returns the address in `This` starting with the index. ~~~:at (n-na)   &This over + ; ~~~ The `record` word adds the evolved value to a buffer. In this casemy `generation` code will set the buffer to `Next`. ~~~:record (c-)   buffer:add n:inc ; ~~~ And now to tie it all together. Meet `generation`, the longest bitof code in this sample. It has several bits: - setup a new buffer pointing to `Next`   - this also preserves the old buffer - setup a loop for each cell in `This`   - initial loop index at -1, to ensure proper dummy state for first cell  - get length of `This` generation - perform a loop for each item in the generation, updating `Next` as it goes - copy `Next` to `This` using `update`. ~~~:generation (-)   [ &Next buffer:set     #-1 &This s:length     [ at group evolve record ] times drop     update   ] buffer:preserve ; ~~~ The last bit is a helper. It takes a number of generations and displaysthe state, then runs a `generation`. ~~~:generations (n-)   [ display generation ] times ; ~~~ And a text. The output should be:     .###.##.#.#.#.#..#..    .#.#####.#.#.#......    ..##...##.#.#.......    ..##...###.#........    ..##...#.##.........    ..##....###.........    ..##....#.#.........    ..##.....#..........    ..##................    ..##................ ~~~#10 generations ~~~`

## REXX

This REXX version will show (as a default)   40   generations,   or less if the generations of cellular automata repeat.

`/*REXX program generates & displays N generations of one─dimensional cellular automata. */parse arg \$ gens .                               /*obtain optional arguments from the CL*/if    \$=='' |    \$==","  then \$=001110110101010  /*Not specified?  Then use the default.*/if gens=='' | gens==","  then gens=40            /* "      "         "   "   "     "    */    do #=0  for gens                              /* process the  one-dimensional  cells.*/   say  " generation"    right(#,length(gens))       ' '       translate(\$, "#·", 10)   @=0                                                                /* [↓] generation.*/          do j=2  for length(\$) - 1;          x=substr(\$, j-1, 3)     /*obtain the cell.*/          if x==011 | x==101 | x==110  then @=overlay(1, @, j)        /*the cell lives. */                                       else @=overlay(0, @, j)        /* "   "    dies. */          end   /*j*/    if [email protected]  then do;  say right('repeats', 40);  leave;  end          /*does it repeat? */   [email protected]                                           /*now use the next generation of cells.*/   end       /*#*/                               /*stick a fork in it,  we're all done. */`

output when using the default input:

``` generation  0   ··###·##·#·#·#·
generation  1   ··#·#####·#·#··
generation  2   ···##···##·#···
generation  3   ···##···###····
generation  4   ···##···#·#····
generation  5   ···##····#·····
generation  6   ···##··········
repeats
```

## Ring

` # Project : One-dimensional cellular automata rule = ["0", "0", "0", "1", "0", "1", "1", "0"]now = "01110110101010100100" for generation = 0 to 9    see "generation " + generation + ": " + now + nl    nxt = ""    for cell = 1 to len(now)        str = "bintodec(" + '"' +substr("0"+now+"0", cell, 3) + '"' + ")"        eval("p=" + str)         nxt = nxt + rule[p+1]    next     temp = nxt    nxt = now    now = tempnext  func bintodec(bin)     binsum = 0     for n=1  to len(bin)         binsum = binsum + number(bin[n]) *pow(2, len(bin)-n)     next     return binsum `

Output:

```generation 0: 01110110101010100100
generation 1: 01011111010101000000
generation 2: 00110001101010000000
generation 3: 00110001110100000000
generation 4: 00110001011000000000
generation 5: 00110000111000000000
generation 6: 00110000101000000000
generation 7: 00110000010000000000
generation 8: 00110000000000000000
generation 9: 00110000000000000000
```

## Ruby

`def evolve(ary)  ([0]+ary+[0]).each_cons(3).map{|a,b,c| a+b+c == 2 ? 1 : 0}end def printit(ary)  puts ary.join.tr("01",".#")end ary = [0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0]printit aryuntil ary == (new = evolve(ary))  printit ary = newend`
Output:
```.###.##.#.#.#.#..#..
.#.#####.#.#.#......
..##...##.#.#.......
..##...###.#........
..##...#.##.........
..##....###.........
..##....#.#.........
..##.....#..........
..##................```

## Rust

`fn get_new_state(windowed: &[bool]) -> bool {    match windowed {        [false, true, true] | [true, true, false] => true,        _ => false    }} fn next_gen(cell: &mut [bool]) {    let mut v = Vec::with_capacity(cell.len());    v.push(cell[0]);    for i in cell.windows(3) {        v.push(get_new_state(i));    }    v.push(cell[cell.len() - 1]);    cell.copy_from_slice(&v);} fn print_cell(cell: &[bool]) {    for v in cell {        print!("{} ", if *v {'#'} else {' '});    }    println!();} fn main() {     const MAX_GENERATION: usize = 10;    const CELLS_LENGTH: usize = 30;     let mut cell: [bool; CELLS_LENGTH] = rand::random();     for i in 1..=MAX_GENERATION {        print!("Gen {:2}: ", i);        print_cell(&cell);        next_gen(&mut cell);    }} `

## Scala

Works with: Scala version 2.8
`def cellularAutomata(s: String) = {  def it = Iterator.iterate(s) ( generation =>    ("_%s_" format generation).iterator     sliding 3     map (_ count (_ == '#'))     map Map(2 -> "#").withDefaultValue("_")     mkString  )   (it drop 1) zip it takeWhile Function.tupled(_ != _) map (_._2) foreach println}`

Sample:

```scala> cellularAutomata("_###_##_#_#_#_#__#__")
_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
```

## Scheme

Works with: Scheme version R${\displaystyle ^{5}}$RS
`(define (next-generation left petri-dish right)  (if (null? petri-dish)      (list)      (cons (if (= (+ left                      (car petri-dish)                      (if (null? (cdr petri-dish))                          right                          (cadr petri-dish)))                   2)                1                0)            (next-generation (car petri-dish) (cdr petri-dish) right)))) (define (display-evolution petri-dish generations)  (if (not (zero? generations))      (begin (display petri-dish)             (newline)             (display-evolution (next-generation 0 petri-dish 0)                                (- generations 1))))) (display-evolution (list 1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0) 10)`

Output:

```(1 1 1 0 1 1 0 1 0 1 0 1 0 1 0 0 1 0)
(1 0 1 1 1 1 1 0 1 0 1 0 1 0 0 0 0 0)
(0 1 1 0 0 0 1 1 0 1 0 1 0 0 0 0 0 0)
(0 1 1 0 0 0 1 1 1 0 1 0 0 0 0 0 0 0)
(0 1 1 0 0 0 1 0 1 1 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0)
(0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0)```

## Seed7

A graphical cellular automaton can be found here.

`\$ include "seed7_05.s7i"; const string: start is "_###_##_#_#_#_#__#__"; const proc: main is func  local    var string: g0 is start;    var string: g1 is start;    var integer: generation is 0;    var integer: i is 0;  begin    writeln(g0);    for generation range 0 to 9 do      for i range 2 to pred(length(g0)) do        if g0[i-1] <> g0[i+1] then          g1 @:= [i] g0[i];        elsif g0[i] = '_' then          g1 @:= [i] g0[i-1];        else          g1 @:= [i] '_'        end if;      end for;      writeln(g1);      g0 := g1;    end for;  end func;`

Output:

```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________
```
==Seed7==

A graphical cellular automaton can be found here.

> petriCache(i) Then stable = False

```           If petriCache(i) Then dead = False
Next
```
```       PetriDish = petriCache
```
```       If dead Then Return PetriStatus.Dead
If stable Then Return PetriStatus.Stable
Return PetriStatus.Active
```
```   End Function
```
```   Private Function BuildDishString(ByVal PetriDish As BitArray) As String
Dim sw As New StringBuilder()
For Each b As Boolean In PetriDish
sw.Append(IIf(b, "#", "_"))
Next
```
```       Return sw.ToString()
End Function
```

End Module

## SequenceL

`import <Utilities/Conversion.sl>; main(args(2)) :=    run(args[1], stringToInt(args[2])) when size(args) = 2 else    "Usage error: exec <initialCells> <generations>"; stringToCells(string(1))[i] := 0 when string[i] = '_' else 1;cellsToString(cells(1))[i] := '#' when cells[i] = 1 else '_';  run(cellsString(1), generations) :=         runHelper(stringToCells(cellsString), generations, cellsString); runHelper(cells(1), generations, result(1)) :=    let        nextCells := step(cells);    in        result when generations = 0    else        runHelper(nextCells, generations - 1,                   result ++ "\n" ++ cellsToString(nextCells)); step(cells(1))[i] :=     let        left := cells[i-1] when i > 1 else 0;        right := cells[i + 1] when i < size(cells) else 0;    in        1 when (left + cells[i] + right) = 2    else        0;`
Output:
```"_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________"
```

## Sidef

Translation of: Perl
`var seq = "_###_##_#_#_#_#__#__";var x = ''; loop {    seq.tr!('01', '_#');    say seq;    seq.tr!('_#', '01');    seq.gsub!(/(?<=(.))(.)(?=(.))/, {|s1,s2,s3| s1 == s3 ? (s1 ? 1-s2 : 0) : s2});    (x != seq) && (x = seq) || break;}`
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
```
Translation of: Raku
`class Automaton(rule, cells) {     method init {        rule = sprintf("%08b", rule).chars.map{.to_i}.reverse;    }     method next {        var previous = cells.map{_};        var len = previous.len;        cells[] = rule[                previous.range.map { |i|                    4*previous[i-1 % len] +                    2*previous[i]         +                      previous[i+1 % len]                }...            ]    }     method to_s {        cells.map { _ ? '#' : ' ' }.join;    }} var size = 10;var auto = Automaton(    rule: 104,    cells: [(size/2).of(0)..., 111011010101.digits..., (size/2).of(0)...],); size.times {    say "|#{auto}|";    auto.next;}`
Output:
```|     ### ## # # #     |
|     # ##### # #      |
|      ##   ## #       |
|      ##   ###        |
|      ##   # #        |
|      ##    #         |
|      ##              |
|      ##              |
|      ##              |
|      ##              |
```

## Tcl

`proc evolve {a} {    set new [list]    for {set i 0} {\$i < [llength \$a]} {incr i} {        lappend new [fate \$a \$i]    }    return \$new} proc fate {a i} {    return [expr {[sum \$a \$i] == 2}]} proc sum {a i} {    set sum 0    set start [expr {\$i - 1 < 0 ? 0 : \$i - 1}]    set end [expr {\$i + 1 >= [llength \$a] ? \$i : \$i + 1}]    for {set j \$start} {\$j <= \$end} {incr j} {        incr sum [lindex \$a \$j]            }    return \$sum} proc print {a} {    puts [string map {0 _ 1 #} [join \$a ""]]} proc parse {s} {    return [split [string map {_ 0 # 1} \$s] ""]} set array [parse "_###_##_#_#_#_#__#__"]print \$arraywhile {[set new [evolve \$array]] ne \$array} {    set array \$new    print \$array}`

## Ursala

Three functions are defined. Rule takes a neighborhood of three cells to the succeeding value of the middle one, step takes a list of cells to its successor by applying the rule across a sliding window, and evolve takes an initial list of cells to a list of those evolving from it according to the rule. The cells are maintained as a list of booleans (0 and &) but are converted to characters for presentation in the example code.

`#import std#import nat rule = -\$<0,0,0,&,0,&,&,0>@rSS zipp0*ziD iota8 step = rule*+ swin3+ :/0+ --<0> evolve "n" = @iNC ~&x+ rep"n" ^C/[email protected] ~& #show+ example =  ~&?(`#!,`.!)** evolve10 <0,&,&,&,0,&,&,0,&,0,&,0,&,0,0,&,0,0>`

output:

```.###.##.#.#.#..#..
.#.#####.#.#......
..##...##.#.......
..##...###........
..##...#.#........
..##....#.........
..##..............
..##..............
..##..............
..##..............
..##..............```

## Vedit macro language

This implementation writes the calculated patterns into an edit buffer, where the results can viewed and saved into a file if required. The edit buffer also acts as storage during calculations.

`IT("Gen 0: ..###.##.#.#.#.#..#.....")     // initial pattern#9  = Cur_Col for (#8 = 1; #8 < 10; #8++) {             // 10 generations    Goto_Col(7)    Reg_Empty(20)    while (Cur_Col < #9-1) {        if (Match("|{##|!#,#.#,|!###}")==0) {            Reg_Set(20, "#", APPEND)        } else {            Reg_Set(20, ".", APPEND)        }        Char    }    EOL IN    IT("Gen ") Num_Ins(#8, LEFT+NOCR) IT(": ")    Reg_Ins(20)}`

Sample output:

`Gen 0: ..###.##.#.#.#.#..#.....Gen 1: ..#.#####.#.#.#.........Gen 2: ...##...##.#.#..........Gen 3: ...##...###.#...........Gen 4: ...##...#.##............Gen 5: ...##....###............Gen 6: ...##....#.#............Gen 7: ...##.....#.............Gen 8: ...##...................Gen 9: ...##...................`

## Visual Basic .NET

This implementation is run from the command line. The command is followed by a string of either 1's or #'s for an active cell, or 0's or _'s for an inactive one.

`Imports System.Text Module CellularAutomata     Private Enum PetriStatus        Active        Stable        Dead    End Enum     Function Main(ByVal cmdArgs() As String) As Integer        If cmdArgs.Length = 0 Or cmdArgs.Length > 1 Then            Console.WriteLine("Command requires string of either 1s and 0s or #s and _s.")            Return 1        End If         Dim petriDish As BitArray         Try            petriDish = InitialisePetriDish(cmdArgs(0))        Catch ex As Exception            Console.WriteLine(ex.Message)            Return 1        End Try         Dim generation As Integer = 0        Dim ps As PetriStatus = PetriStatus.Active         Do While True            If ps = PetriStatus.Stable Then                Console.WriteLine("Sample stable after {0} generations.", generation - 1)                Exit Do            Else                Console.WriteLine("{0}: {1}", generation.ToString("D3"), BuildDishString(petriDish))                If ps = PetriStatus.Dead Then                    Console.WriteLine("Sample dead after {0} generations.", generation)                    Exit Do                End If            End If             ps = GetNextGeneration(petriDish)            generation += 1        Loop         Return 0    End Function     Private Function InitialisePetriDish(ByVal Sample As String) As BitArray        Dim PetriDish As New BitArray(Sample.Length)        Dim dead As Boolean = True         For i As Integer = 0 To Sample.Length - 1            Select Case Sample.Substring(i, 1)                Case "1", "#"                    PetriDish(i) = True                    dead = False                Case "0", "_"                    PetriDish(i) = False                Case Else                    Throw New Exception("Illegal value in string position " & i)                    Return Nothing            End Select        Next         If dead Then            Throw New Exception("Entered sample is dead.")            Return Nothing        End If         Return PetriDish    End Function     Private Function GetNextGeneration(ByRef PetriDish As BitArray) As PetriStatus        Dim petriCache = New BitArray(PetriDish.Length)        Dim neighbours As Integer        Dim stable As Boolean = True        Dim dead As Boolean = True         For i As Integer = 0 To PetriDish.Length - 1            neighbours = 0            If i > 0 AndAlso PetriDish(i - 1) Then neighbours += 1            If i < PetriDish.Length - 1 AndAlso PetriDish(i + 1) Then neighbours += 1             petriCache(i) = (PetriDish(i) And neighbours = 1) OrElse (Not PetriDish(i) And neighbours = 2)            If PetriDish(i) <> petriCache(i) Then stable = False            If petriCache(i) Then dead = False        Next         PetriDish = petriCache         If dead Then Return PetriStatus.Dead        If stable Then Return PetriStatus.Stable        Return PetriStatus.Active     End Function     Private Function BuildDishString(ByVal PetriDish As BitArray) As String        Dim sw As New StringBuilder()        For Each b As Boolean In PetriDish            sw.Append(IIf(b, "#", "_"))        Next         Return sw.ToString()    End FunctionEnd Module`

Output:

```C:\>CellularAutomata _###_##_#_#_#_#__#__
000: _###_##_#_#_#_#__#__
001: _#_#####_#_#_#______
002: __##___##_#_#_______
003: __##___###_#________
004: __##___#_##_________
005: __##____###_________
006: __##____#_#_________
007: __##_____#__________
008: __##________________
Sample stable after 8 generations.```

## Wart

### Simple

`def (gens n l)  prn l  repeat n    zap! gen l    prn l def (gen l)  with (a nil  b nil  c l.0)    collect nil  # won't insert paren without second token      each x cdr.l        shift! a b c x        yield (next a b c)      yield (next b c nil) def (next a b c)  # next state of b given neighbors a and c  if (and a c)  not.b     (or a c)  b`

Output looks a little ugly:

```ready! type in an expression, then hit enter twice. ctrl-d exits.
gens 5 '(1 1 1 nil 1)

(1 1 1 nil 1)
(1 nil 1 1 nil)
(nil 1 1 1 nil)
(nil 1 nil 1 nil)
(nil nil 1 nil nil)
(nil nil nil nil nil)```

### More sophisticated

Computing the next generation becomes much cleaner once you invest a few LoC in a new datatype.

`def (uca l)  # new datatype: Uni-dimensional Cellular Automaton  (tag uca (list l len.l)) def (len l) :case (isa uca l)  # how to compute its length  rep.l.1 defcoerce uca list  # how to convert it to a list  (fn(_) rep._.0) def (pr l) :case (isa uca l)  # how to print it  each x l  # transparently coerces to a list for iterating over    pr (if x "#" "_") # (l i) returns ith cell when l is a uca, and nil when i is out-of-boundsdefcall uca (l i)  if (0 <= i < len.l)    rep.l.0.i def (gens n l)  prn l  repeat n    zap! gen l    prn l def (gen l)  uca+collect+for i 0 (i < len.l) ++i    yield (next  (l i-1)  l.i  (l i+1)) # next state of b, given neighbors a and cdef (next a b c)  if (and a c) not.b     (or a c)  b`

Output is prettier now:

```ready! type in an expression, then hit enter twice. ctrl-d exits.
gens 10 (uca '(nil 1 1 1 nil 1 1 nil 1 nil 1 nil 1 nil 1 nil nil 1 nil nil))

_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
__##________________
__##________________```

## Wren

Translation of: Kotlin
`var trans = "___#_##_" var v = Fn.new { |cell, i| (cell[i] != "_") ? 1 : 0 } var evolve = Fn.new { |cell, backup|    var len = cell.count - 2    var diff = 0    for (i in 1...len) {        /* use left, self, right as binary number bits for table index */        backup[i] = trans[v.call(cell, i - 1) * 4 + v.call(cell, i) * 2 + v.call(cell, i + 1)]        diff = diff + ((backup[i] != cell[i]) ? 1 : 0)    }    cell.clear()    cell.addAll(backup)    return diff != 0} var c = "_###_##_#_#_#_#__#__".toListvar b = "____________________".toListwhile(true) {    System.print(c[1..-1].join())    if (!evolve.call(c,b)) break}`
Output:
```###_##_#_#_#_#__#__
#_#####_#_#_#______
_##___##_#_#_______
_##___###_#________
_##___#_##_________
_##____###_________
_##____#_#_________
_##_____#__________
_##________________
```

## XPL0

`code ChOut=8, CrLf=9;int  Gen, Now, New, I;[Now:= \$076A_A400;for Gen:= 1 to 10 do    [for I:= 31 downto 0 do ChOut(0, if Now & 1<<I then ^# else ^_);    CrLf(0);    New:= 0;    for I:= 30 downto 1 do        case Now>>(I-1) & 7 of %011, %101, %110: New:= New ! 1<<I other;    Now:= New;    ];]`
Output:
```_____###_##_#_#_#_#__#__________
_____#_#####_#_#_#______________
______##___##_#_#_______________
______##___###_#________________
______##___#_##_________________
______##____###_________________
______##____#_#_________________
______##_____#__________________
______##________________________
______##________________________
```

## Yabasic

Translation of: Locomotive_Basic
`10 n=10:READ w:DIM x(w+1),x2(w+1):FOR i=1 to w:READ x(i):NEXT20 FOR k=1 TO n30 FOR j=1 TO w40 IF x(j) THEN PRINT "#"; ELSE PRINT "_"; END IF50 IF x(j-1)+x(j)+x(j+1)=2 THEN x2(j)=1 ELSE x2(j)=0 END IF60 NEXT:PRINT70 FOR j=1 TO w:x(j)=x2(j):NEXT80 NEXT90 DATA 20,0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0`

Other solution

`start\$ = "0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0" dim x\$(1) for k = 1 to 10    n = token(start\$, x\$(), ",")    redim x\$(n+1)    start\$ = ""    for j = 1 to n        if val(x\$(j)) then print "#"; else print "_"; end if        test = abs(val(x\$(j-1)) + val(x\$(j)) + val(x\$(j+1)) = 2)        start\$ = start\$ + str\$(test) + ","    next j    printnext k`

## zkl

Translation of: Groovy
`fcn life1D(line){   right:=line[1,*] + False;           // shift left, False fill   left :=T(False).extend(line[0,-1]); // shift right   left.zip(line,right).apply(fcn(hood){ hood.sum(0)==2 });}`
`chars:=T("_","#");cells:="_###_##_#_#_#_#__#__".split("").apply('==("#")); //-->L(False,True,True,True,False...)do(10){ cells.apply(chars.get).concat().println(); cells=life1D(cells); }`

Or, using strings instead of lists:

`fcn life1D(line){   right:=line[1,*] + "_";  // shift left, "_" fill   left :="_" + line[0,-1]; // shift right   Utils.Helpers.zipWith(      fcn(a,b,c){ (String(a,b,c) - "_") == "##" and "#" or "_" },      left,line,right).concat();}`
`cells:="_###_##_#_#_#_#__#__";do(10){ cells.println(); cells=life1D(cells); }`
Output:
```_###_##_#_#_#_#__#__
_#_#####_#_#_#______
__##___##_#_#_______
__##___###_#________
__##___#_##_________
__##____###_________
__##____#_#_________
__##_____#__________
__##________________
```

/pre>