# Rock-paper-scissors

Rock-paper-scissors
You are encouraged to solve this task according to the task description, using any language you may know.

Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player.

Rock Paper Scissors is a two player game.

Each player chooses one of rock, paper or scissors, without knowing the other player's choice.

The winner is decided by a set of rules:

•   Rock beats scissors
•   Scissors beat paper
•   Paper beats rock

If both players choose the same thing, there is no winner for that round.

For this task, the computer will be one of the players.

The operator will select Rock, Paper or Scissors and the computer will keep a record of the choice frequency, and use that information to make a weighted random choice in an attempt to defeat its opponent.

Extra credit

`with Ada.Text_IO; with Ada.Numerics.Float_Random; procedure Rock_Paper_Scissors is    package Rand renames Ada.Numerics.Float_Random;   Gen: Rand.Generator;    type Choice is (Rock, Paper, Scissors);    Cnt: array (Choice) of Natural := (1, 1, 1);     -- for the initialization: pretend that each of Rock, Paper,      -- and Scissors, has been played once by the human     -- else the first computer choice would be deterministic    function Computer_Choice return Choice is      Random_Number: Natural :=        Integer(Rand.Random(Gen)          * (Float(Cnt(Rock)) + Float(Cnt(Paper)) + Float(Cnt(Scissors))));   begin      if Random_Number < Cnt(Rock) then         -- guess the human will choose Rock         return Paper;      elsif Random_Number - Cnt(Rock) < Cnt(Paper) then         -- guess the human will choose Paper         return Scissors;      else -- guess the human will choose Scissors         return Rock;      end if;   end Computer_Choice;    Finish_The_Game: exception;    function Human_Choice return Choice is      Done: Boolean := False;      T: constant String        := "enter ""r"" for Rock, ""p"" for Paper, or ""s"" for Scissors""!";      U: constant String        := "or enter ""q"" to Quit the game";      Result: Choice;   begin      Ada.Text_IO.Put_Line(T);      Ada.Text_IO.Put_Line(U);      while not Done loop         Done := True;         declare            S: String := Ada.Text_IO.Get_Line;         begin            if S="r" or S="R" then               Result := Rock;            elsif S="p" or S = "P" then               Result := Paper;            elsif S="s" or S="S" then               Result := Scissors;            elsif S="q" or S="Q" then               raise Finish_The_Game;            else               Done := False;            end if;         end;      end loop;      return Result;   end Human_Choice;    type Result is (Human_Wins, Draw, Computer_Wins);    function "<" (X, Y: Choice) return Boolean is      -- X < Y if X looses against Y   begin      case X is         when Rock => return  (Y = Paper);         when Paper => return (Y = Scissors);         when Scissors => return (Y = Rock);      end case;   end "<";    Score: array(Result) of Natural := (0, 0, 0);    C,H: Choice;    Res: Result; begin   -- play the game   loop      C := Computer_Choice;  -- the computer makes its choice first      H := Human_Choice;     -- now ask the player for his/her choice      Cnt(H) := Cnt(H) + 1;  -- update the counts for the AI      if C < H then         Res := Human_Wins;      elsif H < C then         Res := Computer_Wins;      else         Res := Draw;      end if;      Ada.Text_IO.Put_Line("COMPUTER'S CHOICE: " & Choice'Image(C)                             & "       RESULT: " & Result'Image(Res));      Ada.Text_IO.New_Line;      Score(Res) := Score(Res) + 1;   end loop; exception   when Finish_The_Game =>      Ada.Text_IO.New_Line;      for R in Score'Range loop         Ada.Text_IO.Put_Line(Result'Image(R) & Natural'Image(Score(R)));      end loop;end Rock_Paper_Scissors;`

First and last few lines of the output of a game, where the human did permanently choose Rock:

```./rock_paper_scissors
enter "r" for Rock, "p" for Paper, or "s" for Scissors"!
or enter "q" to Quit the game
r
COMPUTER'S CHOICE: SCISSORS       RESULT: HUMAN_WINS

enter "r" for Rock, "p" for Paper, or "s" for Scissors"!
or enter "q" to Quit the game
r
COMPUTER'S CHOICE: ROCK       RESULT: DRAW

enter "r" for Rock, "p" for Paper, or "s" for Scissors"!
or enter "q" to Quit the game
r
COMPUTER'S CHOICE: SCISSORS       RESULT: HUMAN_WINS

enter "r" for Rock, "p" for Paper, or "s" for Scissors"!
or enter "q" to Quit the game
r
COMPUTER'S CHOICE: ROCK       RESULT: DRAW

[...]

enter "r" for Rock, "p" for Paper, or "s" for Scissors"!
or enter "q" to Quit the game
r
COMPUTER'S CHOICE: ROCK       RESULT: DRAW

enter "r" for Rock, "p" for Paper, or "s" for Scissors"!
or enter "q" to Quit the game
r
COMPUTER'S CHOICE: PAPER       RESULT: COMPUTER_WINS

enter "r" for Rock, "p" for Paper, or "s" for Scissors"!
or enter "q" to Quit the game
q

HUMAN_WINS 2
DRAW 5
COMPUTER_WINS 21```

## Aime

`textcomputer_play(record plays, record beats){    integer a, c, total;    text s;     total = plays["rock"] + plays["paper"] + plays["scissors"];    a = drand(total - 1);    for (s, c in plays) {        if (a < c) {            break;        }        a -= c;    }     beats[s];} integermain(void){    integer computer, human;    record beats, plays;    file f;    text s;     computer = human = 0;     f.stdin;     beats["rock"] = "paper";    beats["paper"] = "scissors";    beats["scissors"] = "rock";     plays["rock"] = 1;    plays["paper"] = 1;    plays["scissors"] = 1;     while (1) {        o_text("Your choice [rock/paper/scissors]:\n");        if (f.line(s) == -1) {            break;        }         if (!plays.key(s)) {            o_text("Invalid choice, try again\n");        } else {            text c;             c = computer_play(plays, beats);             o_form("Human: ~, Computer: ~\n", s, c);             if (s == c) {                o_text("Draw\n");            } elif (c == beats[s]) {                computer += 1;                o_text("Computer wins\n");            } else {                human += 1;                o_text("Human wins\n");            }             plays.up(s);             o_form("Score: Human: ~, Computer: ~\n", human, computer);        }    }     return 0;}`

## ALGOL 68

`BEGIN    # rock/paper/scissors game                                             #    # counts of the number of times the player has chosen each move        #    # we initialise each to 1 so that the total isn't zero when we are     #    # choosing the computer's first move (as in the Ada version)           #    INT    r count := 1;    INT    p count := 1;    INT    s count := 1;    # counts of how many games the player and computer have won            #    INT    player count   := 0;    INT    computer count := 0;    print( ( "rock/paper/scissors", newline, newline ) );    WHILE        CHAR player move;        # get the players move - r => rock, p => paper, s => scissors      #        #                        q => quit                                 #        WHILE            print( ( "Please enter your move (r/p/s) or q to quit: " ) );            read( ( player move, newline ) );            (   player move /= "r"            AND player move /= "p"            AND player move /= "s"            AND player move /= "q"            )        DO            print( ( "Unrecognised move", newline ) )        OD;        # continue playing until the player chooses quit                   #        player move /= "q"    DO        # decide the computer's move based on the player's history         #        CHAR  computer move;        INT   move count     = r count + p count + s count;        # predict player will play rock  if the random number              #        #     is in the range 0 .. rock / total                            #        # predict player will play paper if the random number              #        #     is in the range rock / total .. ( rock + paper ) / total     #        # predict player will play scissors otherwise                      #        REAL  r limit        = r count / move count;        REAL  p limit        = r limit + ( p count / move count );        REAL  random move    = next random;        IF    random move < r limit THEN            # we predict the player will choose rock - we choose paper     #            computer move := "p"        ELIF  random move < p limit THEN            # we predict the player will choose paper - we choose scissors #            computer move := "s"        ELSE            # we predict the player will choose scissors - we choose rock  #            computer move := "r"        FI;        print( ( "You chose: " + player   move, newline ) );        print( ( "I   chose: " + computer move, newline ) );        IF   player move = computer move THEN            # both players chose the same - draw                           #            print( ( "We draw", newline ) )        ELSE            # players chose different moves - there is a winner            #            IF ( player move = "r" AND computer move = "s" )            OR ( player move = "p" AND computer move = "r" )            OR ( player move = "s" AND computer move = "p" )            THEN                player count +:= 1;                print( ( "You win", newline ) )            ELSE                computer count +:= 1;                print( ( "I win",   newline ) )            FI;            print( ( "You won: "                   , whole( player count  , 0 )                   , ", I won: "                   , whole( computer count, 0 )                   , newline                   )                 )        FI;        IF   player move = "r" THEN            # player chose rock                                            #            r count +:= 1        ELIF player move = "p" THEN            # player chose paper                                           #            p count +:= 1        ELSE            # player chose scissors                                        #            s count +:= 1        FI    OD;    print( ( "Thanks for a most enjoyable game", newline ) )END`

## AutoHotkey

`DllCall("AllocConsole")Write("Welcome to Rock-Paper-Scissors`nMake a choice: ") cR := cP := cS := 0 ; user choice countuserChoice := Read()Write("My choice: " . cpuChoice := MakeChoice(1, 1, 1)) Loop{	Write(DecideWinner(userChoice, cpuChoice) . "`nMake A Choice: ")	cR += SubStr(userChoice, 1, 1) = "r", cP += InStr(userChoice, "P"), cS += InStr(userChoice, "S")	userChoice := Read()	Write("My Choice: " . cpuChoice := MakeChoice(cR, cP, cS))} MakeChoice(cR, cP, cS){	; parameters are number of times user has chosen each item	total := cR + cP + cS 	Random, rand, 0.0, 1.0	if (rand >= 0 and rand <= cR / total)		return "Paper"	else if (rand > cR / total and rand <= (cR + cP) / total)		return "Scissors"	else		return "Rock"} DecideWinner(user, cpu){	user := SubStr(user, 1, 1), cpu := SubStr(cpu, 1, 1)	if (user = cpu)		return "`nTie!"	else if (user = "r" and cpu = "s") or (user = "p" and cpu = "r") or (user = "s" and cpu = "p")		return "`nYou Win!"	else		return "`nI Win!"} Read(){	FileReadLine, a, CONIN\$, 1	return a}Write(txt){	FileAppend, % txt, CONOUT\$}`

## AutoIt

I´ve created a GUI to play and show results, no Console Input

` RPS() Func RPS()	Local \$ai_Played_games[4]	\$ai_Played_games[0] = 3	For \$I = 1 To 3		\$ai_Played_games[\$I] = 1	Next	\$RPS = GUICreate("Rock Paper Scissors", 338, 108, 292, 248)	\$Rock = GUICtrlCreateButton("Rock", 8, 8, 113, 25, 131072)	\$Paper = GUICtrlCreateButton("Paper", 8, 40, 113, 25, 131072)	\$Scissors = GUICtrlCreateButton("Scissors", 8, 72, 113, 25, 131072)	\$Label1 = GUICtrlCreateLabel("W:", 136, 8, 18, 17)	\$Wins = GUICtrlCreateLabel("0", 160, 8, 36, 17)	\$Label3 = GUICtrlCreateLabel("L:", 208, 8, 13, 17)	\$Looses = GUICtrlCreateLabel("0", 224, 8, 36, 17)	\$Label5 = GUICtrlCreateLabel("D:", 272, 8, 15, 17)	\$Deuce = GUICtrlCreateLabel("0", 296, 8, 36, 17)	\$Displaybutton = GUICtrlCreateButton("", 136, 48, 193, 49, 131072)	GUICtrlSetState(\$ai_Played_games, 128)	GUISetState(@SW_SHOW)	While 1		\$nMsg = GUIGetMsg()		Switch \$nMsg			Case -3				Exit			Case \$Rock				\$Ret = _RPS_Eval(1, \$ai_Played_games)				GUICtrlSetData(\$Displaybutton, \$Ret)				If \$Ret = "Deuce" Then					GUICtrlSetData(\$Deuce, Guictrlread(\$Deuce)+1)				Elseif \$Ret = "You Loose" Then					GUICtrlSetData(\$Looses, Guictrlread(\$Looses)+1)				Elseif \$Ret = "You Win" Then					GUICtrlSetData(\$Wins, Guictrlread(\$Wins)+1)				EndIf			Case \$Paper				\$Ret = _RPS_Eval(2, \$ai_Played_games)				GUICtrlSetData(\$Displaybutton, \$Ret)				If \$Ret = "Deuce" Then					GUICtrlSetData(\$Deuce, Guictrlread(\$Deuce)+1)				Elseif \$Ret = "You Loose" Then					GUICtrlSetData(\$Looses, Guictrlread(\$Looses)+1)				Elseif \$Ret = "You Win" Then					GUICtrlSetData(\$Wins, Guictrlread(\$Wins)+1)				EndIf			Case \$Scissors				\$Ret = _RPS_Eval(3, \$ai_Played_games)				GUICtrlSetData(\$Displaybutton, \$Ret)				If \$Ret = "Deuce" Then					GUICtrlSetData(\$Deuce, Guictrlread(\$Deuce)+1)				Elseif \$Ret = "You Loose" Then					GUICtrlSetData(\$Looses, Guictrlread(\$Looses)+1)				Elseif \$Ret = "You Win" Then					GUICtrlSetData(\$Wins, Guictrlread(\$Wins)+1)				EndIf		EndSwitch	WEnd EndFunc   ;==>RPS Func _RPS_Eval(\$i_Player_Choose, \$ai_Played_games)	Local \$i_choice = 1	\$i_rnd = Random(1, 1000, 1)	\$i_choose_1 = (\$ai_Played_games[1] / \$ai_Played_games[0] * 1000)	\$i_choose_2 = (\$ai_Played_games[2] / \$ai_Played_games[0] * 1000)	\$i_choose_3 = (\$ai_Played_games[3] / \$ai_Played_games[0] * 1000)	If \$i_rnd < \$i_choose_1 Then		\$i_choice = 2	ElseIf \$i_rnd < \$i_choose_1 + \$i_choose_2 And \$i_rnd > \$i_choose_1 Then		\$i_choice = 3	ElseIf \$i_rnd < \$i_choose_1 + \$i_choose_2 + \$i_choose_3 And \$i_rnd > \$i_choose_1 + \$i_choose_2 Then		\$i_choice = 1	EndIf	\$ai_Played_games[0] += 1	If \$i_Player_Choose = 1 Then		\$ai_Played_games[1] += 1		If \$i_choice = 1 Then Return "Deuce"		If \$i_choice = 2 Then Return "You Loose"		If \$i_choice = 3 Then Return "You Win"	ElseIf \$i_Player_Choose = 2 Then		\$ai_Played_games[2] += 1		If \$i_choice = 2 Then Return "Deuce"		If \$i_choice = 3 Then Return "You Loose"		If \$i_choice = 1 Then Return "You Win"	ElseIf \$i_Player_Choose = 3 Then		\$ai_Played_games[3] += 1		If \$i_choice = 3 Then Return "Deuce"		If \$i_choice = 1 Then Return "You Loose"		If \$i_choice = 2 Then Return "You Win"	EndIfEndFunc   ;==>_RPS_Eval  `

## BASIC

Works with: QBasic
`DIM pPLchoice(1 TO 3) AS INTEGER, pCMchoice(1 TO 3) AS INTEGERDIM choices(1 TO 3) AS STRINGDIM playerwins(1 TO 3) AS INTEGERDIM playerchoice AS INTEGER, compchoice AS INTEGERDIM playerwon AS INTEGER, compwon AS INTEGER, tie AS INTEGERDIM tmp AS INTEGER ' Do it this way for QBasic; FreeBASIC supports direct array assignment.DATA "rock", "paper", "scissors"FOR tmp = 1 TO 3    READ choices(tmp)NEXTDATA 3, 1, 2FOR tmp = 1 TO 3    READ playerwins(tmp)NEXT RANDOMIZE TIMER DO    ' Computer chooses first to ensure there's no "cheating".    compchoice = INT(RND * (pPLchoice(1) + pPLchoice(2) + pPLchoice(3) + 3))    SELECT CASE compchoice        CASE 0 TO (pPLchoice(1))            ' Player past choice: rock; choose paper.            compchoice = 2        CASE (pPLchoice(1) + 1) TO (pPLchoice(1) + pPLchoice(2) + 1)            ' Player past choice: paper; choose scissors.            compchoice = 3        CASE (pPLchoice(1) + pPLchoice(2) + 2) TO (pPLchoice(1) + pPLchoice(2) + pPLchoice(3) + 2)            ' Player past choice: scissors; choose rock.            compchoice = 1    END SELECT     PRINT "Rock, paper, or scissors ";    DO        PRINT "[1 = rock, 2 = paper, 3 = scissors, 0 to quit]";        INPUT playerchoice    LOOP WHILE (playerchoice < 0) OR (playerchoice > 3)     IF 0 = playerchoice THEN EXIT DO     pCMchoice(compchoice) = pCMchoice(compchoice) + 1    pPLchoice(playerchoice) = pPLchoice(playerchoice) + 1    PRINT "You chose "; choices(playerchoice); " and I chose "; choices(compchoice); ". ";    IF (playerchoice) = compchoice THEN        PRINT "Tie!"        tie = tie + 1    ELSEIF (compchoice) = playerwins(playerchoice) THEN        PRINT "You won!"        playerwon = playerwon + 1    ELSE        PRINT "I won!"        compwon = compwon + 1    END IFLOOP PRINT "Some useless statistics:"PRINT "You won "; STR\$(playerwon); " times, and I won "; STR\$(compwon); " times; "; STR\$(tie); " ties."PRINT             ,   choices(1),   choices(2),   choices(3)PRINT "You chose:", pPLchoice(1), pPLchoice(2), pPLchoice(3)PRINT "  I chose:", pCMchoice(1), pCMchoice(2), pCMchoice(3)`

A sample game:

```\$ ./rokpprscr
Rock, paper, or scissors [1 = rock, 2 = paper, 3 = scissors, 0 to quit]? 1
You chose rock and I chose paper. I won!
Rock, paper, or scissors [1 = rock, 2 = paper, 3 = scissors, 0 to quit]? 1
You chose rock and I chose scissors. You won!

[... 56 more times choosing "rock"...]

Rock, paper, or scissors [1 = rock, 2 = paper, 3 = scissors, 0 to quit]? 1
You chose rock and I chose paper. I won!
Rock, paper, or scissors [1 = rock, 2 = paper, 3 = scissors, 0 to quit]? 1
You chose rock and I chose paper. I won!
Rock, paper, or scissors [1 = rock, 2 = paper, 3 = scissors, 0 to quit]? 3
You chose scissors and I chose paper. You won!
Rock, paper, or scissors [1 = rock, 2 = paper, 3 = scissors, 0 to quit]?
Some useless statistics:
You won  5 times, and I won  54 times;  2 ties.
rock          paper         scissors
You chose:     60            0             1
I chose:     2             55            4
```

## Bash

`#!/bin/bashecho "What will you choose? [rock/paper/scissors]"read responseaiThought=\$(echo \$[ 1 + \$[ RANDOM % 3  ]])case \$aiThought in	1) 	 aiResponse="rock"   ;;	2) 	 aiResponse="paper" ;;	3)  	 aiResponse="scissors"  ;;esacecho "AI - \$aiResponse"responses="\$response\$aiResponse"case \$responses in	rockrock)  isTie=1  ;;	rockpaper)  playerWon=0  ;;	rockscissors)  playerWon=1  ;;	paperrock)  playerWon=1  ;;	paperpaper)  isTie=1  ;;	paperscissors)  playerWon=0  ;;	scissorsrock)  playerWon=0  ;;	scissorspaper)  playerWon=1  ;;	scissorsscissors)  isTie=1  ;;esacif [[ \$isTie == 1 ]] ; then echo "It's a tie!" && exit 1 ; fiif [[ \$playerWon == 0 ]] ; then echo "Sorry, \$aiResponse beats \$response , try again.." && exit 1 ; fiif [[ \$playerWon == 1 ]] ; then echo "Good job, \$response beats \$aiResponse!" && exit 1 ; fi`

## Batch File

` @echo offsetlocal enabledelayedexpansion set choice1=rockset choice2=paperset choice3=scissorsset freq1=0set freq2=0set freq3=0set games=0set won=0set lost=0set tie=0 :start clsecho Games - %games% : Won - %won% : Lost - %lost% : Ties - %tie%choice /c RPS /n /m "[R]ock, [P]aper or [S]cissors? " set /a choicequant+=1set choice=%errorlevel%set /a rocklimit=100 / %choicequant% * %freq3%set /a scissorslimit=100 - (100 / %choicequant% * %freq2%)set /a randchoice=%random% %% 100 + 1set compchoice=2if %randchoice% geq %scissorslimit% set compchoice=3if %randchoice% leq %rocklimit% set compchoice=1 clsecho Player: !choice%choice%! ^|vs^| Computer: !choice%compchoice%!goto %compchoice% :1 if %choice%==1 goto tieif %choice%==2 goto winif %choice%==3 goto loss :2 if %choice%==1 goto lossif %choice%==2 goto tieif %choice%==3 goto win :3 if %choice%==1 goto winif %choice%==2 goto lossif %choice%==3 goto tie :winset /a won+=1echo Player wins^!goto end :lossset /a lost+=1echo Computer Wins^!goto end :tieset /a tie+=1echo Tie^!goto end :endset /a games+=1set /a freq%choice%+=1pausegoto start `

## BBC BASIC

`PRINT"Welcome to the game of rock-paper-scissors"PRINT "Each player guesses one of these three, and reveals it at the same time."PRINT "Rock blunts scissors, which cut paper, which wraps stone."PRINT "If both players choose the same, it is a draw!"PRINT "When you've had enough, choose Q."DIM rps%(2),g\$(3)g\$()="rock","paper","scissors"total%=0draw%=0pwin%=0cwin%=0c%=RND(3)PRINT"What is your move (press R, P, or S)?"REPEAT  REPEAT q\$=GET\$ UNTIL INSTR("RPSrpsQq",q\$)>0  g%=(INSTR("RrPpSsQq",q\$)-1) DIV 2  IF g%>2 THEN PROCsummarise:END  total%+=1  rps%(g%)+=1  PRINT"You chose ";g\$(g%);" and I chose ";g\$(c%);  CASE g%-c% OF    WHEN 0:      PRINT ". It's a draw"      draw%+=1    WHEN 1,-2:      PRINT ". You win!"      pwin%+=1    WHEN -1,2:      PRINT ". I win!"      cwin%+=1    ENDCASE  c%=FNmove(rps%(),total%)UNTIL FALSEEND:DEFPROCsummarisePRINT "You won ";pwin%;", and I won ";cwin%;". There were ";draw%;" draws"PRINT "Thanks for playing!"ENDPROC:DEFFNmove(p%(),t%)LOCAL r%r%=RND(total%)IF r%<=p%(0) THEN =1IF r%<=p%(0)+p%(1) THEN =2=0`

Sample output:

```Welcome to the game of rock-paper-scissors
Each player guesses one of these three, and reveals it at the same time.
Rock blunts scissors, which cut paper, which wraps stone.
If both players choose the same, it is a draw!
When you've had enough, choose Q.
What is your move (press R, P, or S)?
You chose rock and I chose paper. I win!
You chose scissors and I chose paper. You win!
You chose scissors and I chose paper. You win!
You chose scissors and I chose paper. You win!
You chose scissors and I chose paper. You win!
You chose scissors and I chose rock. I win!
You chose paper and I chose paper. It's a draw
You chose paper and I chose rock. You win!
You chose paper and I chose rock. You win!
You chose paper and I chose paper. It's a draw
You chose paper and I chose paper. It's a draw
You chose paper and I chose rock. You win!
You chose scissors and I chose rock. I win!
You chose scissors and I chose scissors. It's a draw
You chose scissors and I chose rock. I win!
You chose scissors and I chose scissors. It's a draw
You chose scissors and I chose rock. I win!
You won 7, and I won 5. There were 5 draws
Thanks for playing!```

## C

` #include <stdio.h>#include <stdlib.h>#define LEN 3  /* pick a random index from 0 to n-1, according to probablities listed   in p[] which is assumed to have a sum of 1. The values in the probablity   list matters up to the point where the sum goes over 1 */int rand_idx(double *p, int n){	double s = rand() / (RAND_MAX + 1.0);	int i;	for (i = 0; i < n - 1 && (s -= p[i]) >= 0; i++);	return i;} int main(){	int user_action, my_action;	int user_rec[] = {0, 0, 0};	const char *names[] = { "Rock", "Paper", "Scissors" };	char str[2];	const char *winner[] = { "We tied.", "Meself winned.", "You win." };	double  p[LEN] = { 1./3, 1./3, 1./3 }; 	while (1) {		my_action = rand_idx(p,LEN); 		printf("\nYour choice [1-3]:\n"			"  1. Rock\n  2. Paper\n  3. Scissors\n> "); 		/* scanf is a terrible way to do input.  should use stty and keystrokes */		if (!scanf("%d", &user_action)) {			scanf("%1s", str);			if (*str == 'q') {				printf("Your choices [rock : %d , paper :  %d , scissors %d] ",user_rec[0],user_rec[1], user_rec[2]); 				return 0;			}			continue;		}		user_action --;		if (user_action > 2 || user_action < 0) {			printf("invalid choice; again\n");			continue;		}		printf("You chose %s; I chose %s. %s\n",			names[user_action], names[my_action],			winner[(my_action - user_action + 3) % 3]); 		user_rec[user_action]++;	}} `

Here's another code: (Does it using a while loop)

` #include <stdio.h> // Standard IO#include <stdlib.h> // other stuff#include <time.h>#include <string.h> //This should add weighted random function to "The Elite Noob"'s code, stolen from above code because it does calculation so well//closest I could make it to original but without pointless attempt to make code look smaller than above code by putting code on the same lines int rand_i(int n){	int rand_max = RAND_MAX - (RAND_MAX % n);	int ret;	while ((ret = rand()) >= rand_max);	return ret/(rand_max / n);} int weighed_rand(int *tbl, int len){	int i, sum, r;	for (i = 0, sum = 0; i < len; sum += tbl[i++]);	if (!sum) return rand_i(len); 	r = rand_i(sum) + 1;	for (i = 0; i < len && (r -= tbl[i]) > 0; i++);	return i;}   int main(int argc, const char *argv[]){	char umove[10], cmove[10], line[255];	int user, comp;	int tbl[]={0,0,0};	int tbllen=3;	printf("Hello, Welcome to rock-paper-scissors\nBy The Elite Noob\n");mainloop:	while(1)	{ // infinite loop :)		printf("\n\nPlease type in 1 for Rock, 2 For Paper, 3 for Scissors, 4 to quit\n");		srand(time(NULL));		comp = (weighed_rand(tbl, tbllen) + 1) % 3;		fgets(line, sizeof(line), stdin);			while(sscanf(line, "%d", &user) != 1) //1 match of defined specifier on input line		{   			printf("You have not entered an integer.\n");			fgets(line, sizeof(line), stdin);		}						if( (user > 4) || (user < 1) )		{			printf("Please enter a valid number!\n");			continue;		}		switch (comp)		{			case 1 :				strcpy(cmove, "Rock");				break;			case 2 :				strcpy(cmove, "Paper");				break;			case 3 :				strcpy(cmove, "Scissors");				break;			default :				printf("Computer Error, set comp=1\n");				comp=1;				strcpy(cmove, "Rock");				break;		}		switch (user)		{			case 1 :				strcpy(umove, "Rock");				break;			case 2 :				strcpy(umove, "Paper");				break;			case 3 :				strcpy(umove, "Scissors");				break;			case 4 :				printf("Goodbye! Thanks for playing!\n");				return 0;			default :				printf("Error, user number not between 1-4 exiting...");				goto mainloop;		}		if( (user+1)%3 == comp )		{			printf("Comp Played: %s\nYou Played: %s\nSorry, You Lost!\n", cmove, umove);		}			else if(comp == user)		{			printf("Comp Played: %s\nYou Played: %s\nYou Tied :p\n", cmove, umove);		}		else		{			printf("Comp Played: %s\nYou Played: %s\nYay, You Won!\n", cmove, umove);		}		tbl[user-1]++;	}} `

## C++

` #include <windows.h>#include <iostream>#include <string> //-------------------------------------------------------------------------------using namespace std; //-------------------------------------------------------------------------------enum choices { ROCK, SPOCK, PAPER, LIZARD, SCISSORS, MX_C };enum indexes { PLAYER, COMPUTER, DRAW }; //-------------------------------------------------------------------------------class stats{public:    stats() : _draw( 0 )    {        ZeroMemory( _moves, sizeof( _moves ) );	ZeroMemory( _win, sizeof( _win ) );    }    void draw()		        { _draw++; }    void win( int p )	        { _win[p]++; }    void move( int p, int m )   { _moves[p][m]++; }    int getMove( int p, int m ) { return _moves[p][m]; }    string format( int a )    {	char t[32];	wsprintf( t, "%.3d", a );	string d( t );	return d;    }     void print()    {        string  d = format( _draw ),	       pw = format( _win[PLAYER] ),		cw = format( _win[COMPUTER] ),	       pr = format( _moves[PLAYER][ROCK] ),	cr = format( _moves[COMPUTER][ROCK] ),               pp = format( _moves[PLAYER][PAPER] ),	cp = format( _moves[COMPUTER][PAPER] ),	       ps = format( _moves[PLAYER][SCISSORS] ), cs = format( _moves[COMPUTER][SCISSORS] ),	       pl = format( _moves[PLAYER][LIZARD] ),	cl = format( _moves[COMPUTER][LIZARD] ),	       pk = format( _moves[PLAYER][SPOCK] ),	ck = format( _moves[COMPUTER][SPOCK] ); 	system( "cls" );	cout << endl;	cout << "+----------+-------+--------+--------+---------+----------+--------+---------+" << endl;	cout << "|          |  WON  |  DRAW  |  ROCK  |  PAPER  | SCISSORS | LIZARD |  SPOCK  |" << endl;	cout << "+----------+-------+--------+--------+---------+----------+--------+---------+" << endl;	cout << "|  PLAYER  |  "  << pw << "  |        |   " << pr << "  |   " << pp << "   |   " << ps << "    |  " << pl << "   |   " << pk << "   |" << endl;	cout << "+----------+-------+   " << d << "  +--------+---------+----------+--------+---------+" << endl;	cout << "| COMPUTER |  "  << cw << "  |        |   " << cr << "  |   " << cp << "   |   " << cs << "    |  " << cl << "   |   " << ck << "   |" << endl;	cout << "+----------+-------+--------+--------+---------+----------+--------+---------+" << endl;	cout << endl << endl; 	system( "pause" );     } private:    int _moves[2][MX_C], _win[2], _draw;};//-------------------------------------------------------------------------------class rps{private:    int makeMove()    {	int total = 0, r, s;	for( int i = 0; i < MX_C; total += statistics.getMove( PLAYER, i++ ) );	r = rand() % total; 	for( int i = ROCK; i < SCISSORS; i++ )	{	    s = statistics.getMove( PLAYER, i );	    if( r < s ) return ( i + 1 );	    r -= s;	} 	return ROCK;    }     void printMove( int p, int m )    {	if( p == COMPUTER ) cout << "My move: ";	else cout << "Your move: "; 	switch( m )	{	    case ROCK: cout << "ROCK\n"; break;	    case PAPER: cout << "PAPER\n"; break;	    case SCISSORS: cout << "SCISSORS\n"; break;	    case LIZARD: cout << "LIZARD\n"; break;	    case SPOCK: cout << "SPOCK\n";	}    } public:    rps()    {	checker[ROCK][ROCK] = 2; checker[ROCK][PAPER] = 1; checker[ROCK][SCISSORS] = 0; checker[ROCK][LIZARD] = 0; checker[ROCK][SPOCK] = 1;	checker[PAPER][ROCK] = 0; checker[PAPER][PAPER] = 2; checker[PAPER][SCISSORS] = 1; checker[PAPER][LIZARD] = 1; checker[PAPER][SPOCK] = 0;	checker[SCISSORS][ROCK] = 1; checker[SCISSORS][PAPER] = 0; checker[SCISSORS][SCISSORS] = 2; checker[SCISSORS][LIZARD] = 0; checker[SCISSORS][SPOCK] = 1;	checker[LIZARD][ROCK] = 1; checker[LIZARD][PAPER] = 0; checker[LIZARD][SCISSORS] = 1; checker[LIZARD][LIZARD] = 2; checker[LIZARD][SPOCK] = 0;	checker[SPOCK][ROCK] = 0; checker[SPOCK][PAPER] = 1; checker[SPOCK][SCISSORS] = 0; checker[SPOCK][LIZARD] = 1; checker[SPOCK][SPOCK] = 2;    }    void play()    {	int p, r, m;	while( true )	{	    cout << "What is your move (1)ROCK (2)SPOCK (3)PAPER (4)LIZARD (5)SCISSORS (0)Quit ? ";	    cin >> p;	    if( !p || p < 0 ) break;	    if( p > 0 && p < 6 )	    {		p--;		cout << endl;		printMove( PLAYER, p );		statistics.move( PLAYER, p ); 		m = makeMove();		statistics.move( COMPUTER, m );		printMove( COMPUTER, m ); 		r = checker[p][m];		switch( r )		{		    case DRAW: 		        cout << endl << "DRAW!" << endl << endl; 		        statistics.draw();		    break;		    case COMPUTER: 			cout << endl << "I WIN!" << endl << endl;  			statistics.win( COMPUTER );		    break;		    case PLAYER: 			cout << endl << "YOU WIN!" << endl << endl; 			statistics.win( PLAYER ); 		}		system( "pause" );	    }	    system( "cls" );	}	statistics.print();    } private:    stats statistics;    int checker[MX_C][MX_C];};//-------------------------------------------------------------------------------int main( int argc, char* argv[] ){    srand( GetTickCount() );    rps game;    game.play();    return 0;}//------------------------------------------------------------------------------- `

Sample output:

```What is your move (1)ROCK (2)SPOCK (3)PAPER (4)LIZARD (5)SCISSORS (0)Quit ? 1

My move: PAPER

I WIN!

What is your move (1)ROCK (2)SPOCK (3)PAPER (4)LIZARD (5)SCISSORS (0)Quit ? 3

My move: SPOCK

YOU WIN!

What is your move (1)ROCK (2)SPOCK (3)PAPER (4)LIZARD (5)SCISSORS (0)Quit ? 1

My move: LIZARD

I WIN!

[...]

+----------+-------+--------+--------+---------+----------+--------+---------+
|          |  WON  |  DRAW  |  ROCK  |  PAPER  | SCISSORS | LIZARD |  SPOCK  |
+----------+-------+--------+--------+---------+----------+--------+---------+
|  PLAYER  |  001  |        |   003  |   002   |   000    |  000   |   009   |
+----------+-------+   005  +--------+---------+----------+--------+---------+
| COMPUTER |  008  |        |   000  |   005   |   000    |  001   |   008   |
+----------+-------+--------+--------+---------+----------+--------+---------+

```

## C#

`using System;using System.Collections.Generic;using System.Linq; namespace RockPaperScissors{    class Program    {        static void Main(string[] args)        {            // There is no limit on the amount of weapons supported by RPSGame. Matchups are calculated depending on the order.            var rps = new RPSGame("scissors", "paper", "rock", "lizard", "spock");             int wins = 0, losses = 0, draws = 0;             while (true)            {                Console.WriteLine("Make your move: " + string.Join(", ", rps.Weapons) + ", quit");                 string weapon = Console.ReadLine().Trim().ToLower();                 if (weapon == "quit")                    break;                 if (!rps.Weapons.Contains(weapon))                {                    Console.WriteLine("Invalid weapon!");                    continue;                }                 int result = rps.Next(weapon);                 Console.WriteLine("You chose {0} and your opponent chose {1}!", weapon, rps.LastAIWeapon);                 switch (result)                {                    case 1: Console.WriteLine("{0} pwns {1}. You're a winner!", weapon, rps.LastAIWeapon);                        wins++;                        break;                    case 0: Console.WriteLine("Draw!");                        draws++;                        break;                    case -1: Console.WriteLine("{0} pwns {1}. You're a loser!", rps.LastAIWeapon, weapon);                        losses++;                        break;                }                 Console.WriteLine();            }             Console.WriteLine("\nPlayer Statistics\nWins: {0}\nLosses: {1}\nDraws: {2}", wins, losses, draws);        }         class RPSGame        {            public RPSGame(params string[] weapons)            {                Weapons = weapons;                 // Creates a new AI opponent, and gives it the list of weapons.                _rpsAI = new RPSAI(weapons);            }             // Play next turn.            public int Next(string weapon)            {                string aiWeapon = _rpsAI.NextMove(); // Gets the AI opponent's next move.                LastAIWeapon = aiWeapon; // Saves the AI opponent's move in a property so the player can see it.                 _rpsAI.AddPlayerMove(weapon); // Let the AI know which weapon the player chose, for future predictions.                return GetWinner(Weapons, weapon, aiWeapon); // Returns -1 if AI win, 0 if draw, and 1 if player win.            }             // Returns matchup winner.            public static int GetWinner(string[] weapons, string weapon1, string weapon2)            {                if (weapon1 == weapon2)                    return 0; // If weapons are the same, return 0 for draw.                 if (GetVictories(weapons, weapon1).Contains(weapon2))                    return 1; // Returns 1 for weapon1 win.                else if (GetVictories(weapons, weapon2).Contains(weapon1))                    return -1; // Returns -1 for weapon2 win.                 throw new Exception("No winner found.");            }             /*              * Return weapons that the provided weapon beats.             * The are calculated in the following way:             * If the index of the weapon is even, then all even indices less than it,             * and all odd indices greater than it, are victories.             * One exception is if it is an odd index, and also the last index in the set,             * then the first index in the set is a victory.             */            public static IEnumerable<string> GetVictories(string[] weapons, string weapon)            {                // Gets index of weapon.                int index = Array.IndexOf(weapons, weapon);                 // If weapon is odd and the final index in the set, then return the first item in the set as a victory.                if (index % 2 != 0 && index == weapons.Length - 1)                    yield return weapons[0];                 for (int i = index - 2; i >= 0; i -= 2)                    yield return weapons[i];                 for (int i = index + 1; i < weapons.Length; i += 2)                    yield return weapons[i];            }             public string LastAIWeapon            {                private set;                get;            }             public readonly string[] Weapons;            private RPSAI _rpsAI;             class RPSAI            {                public RPSAI(params string[] weapons)                {                    _weapons = weapons;                    _weaponProbability = new Dictionary<string, int>();                     // The AI sets the probability for each weapon to be chosen as 1.                    foreach (string weapon in weapons)                        _weaponProbability.Add(weapon, 1);                     _random = new Random();                }                 // Increases probability of selecting each weapon that beats the provided move.                public void AddPlayerMove(string weapon)                {                    int index = Array.IndexOf(_weapons, weapon);                     foreach (string winWeapon in _weapons.Except(GetVictories(_weapons, weapon)))                        if (winWeapon != weapon)                            _weaponProbability[winWeapon]++;                }                 // Gets the AI's next move.                public string NextMove()                {                    double r = _random.NextDouble();                     double divisor = _weaponProbability.Values.Sum();                     var weightedWeaponRanges = new Dictionary<double, string>();                     double currentPos = 0.0;                     // Maps probabilities to ranges between 0.0 and 1.0. Returns weighted random weapon.                    foreach (var weapon in _weaponProbability)                    {                        double weightedRange = weapon.Value / divisor;                        if (r <= currentPos + (weapon.Value / divisor))                            return weapon.Key;                        currentPos += weightedRange;                    }                     throw new Exception("Error calculating move.");                }                 Random _random;                private readonly string[] _weapons;                private Dictionary<string, int> _weaponProbability;            }        }    }}`

Sample output of first 2 and last 2 rounds when player chooses rock every turn:

```Make your move: scissors, paper, rock, lizard, spock, quit
rock
You chose rock and your opponent chose lizard!
rock pwns lizard. You're a winner!

Make your move: scissors, paper, rock, lizard, spock, quit
rock
You chose rock and your opponent chose lizard!
rock pwns lizard. You're a winner!

...

Make your move: scissors, paper, rock, lizard, spock, quit
rock
You chose rock and your opponent chose paper!
paper pwns rock. You're a loser!

Make your move: scissors, paper, rock, lizard, spock, quit
rock
You chose rock and your opponent chose spock!
spock pwns rock. You're a loser!

Make your move: scissors, paper, rock, lizard, spock, quit
quit

Player Statistics
Wins: 5
Losses: 60
Draws: 1
```

## Clojure

Library: jline

Note: If you run it with Leiningen, use the special trampoline run to prevent issues:

`\$ lein trampoline run`

Code:

`(ns rps.core  (:require [clojure.data.generators :refer [weighted]])  (:import jline.Terminal)  (:gen-class)) (def what-beats {:rock :paper, :paper :scissors, :scissors :rock}) (defn battle [human comp]  (let [h (name human)        c (name comp)]    (cond      (= human comp) (println (format "We both picked %s. DRAW!" c))      (= human (what-beats comp))        (println (format "Your %s defeats computer's %s. YOU WIN!" h c))      (= comp (what-beats human))        (println (format "Computer's %s defeats your %s. YOU LOSE!" c h))      :else (println (format "Wat? %s and %s ?" h c))))) (defn key->rps [k]  (cond    (or (= k 82) (= k 114)) :rock    (or (= k 80) (= k 112)) :paper    (or (= k 83) (= k 115)) :scissors    :else nil)) (defn play-game [freqs]    (println "\n(R)ock, (P)aper, (S)cissors?")    (let [term (Terminal/getTerminal)          rps (key->rps (.readCharacter term System/in))]      (if-not (nil? rps)        (do           (battle rps (what-beats (weighted freqs)))          (recur (assoc freqs rps (inc (rps freqs)))))        (println "Game Over Man!  Game Over!")))) (defn -main  "Rock, Paper, Scissors!"  [& args]  (play-game {:rock 1, :paper 1, :scissors 1}))`
Output:
```(R)ock, (P)aper, (S)cissors?
Your paper defeats computer's rock. YOU WIN!

(R)ock, (P)aper, (S)cissors?
Computer's paper defeats your rock. YOU LOSE!

(R)ock, (P)aper, (S)cissors?
We both picked scissors. DRAW!```

## D

Translation of: Python
`import std.stdio, std.random, std.string, std.conv, std.array, std.typecons; enum Choice { rock, paper, scissors } bool beats(in Choice c1, in Choice c2) pure nothrow @safe @nogc {    with (Choice) return (c1 == paper    && c2 == rock) ||                         (c1 == scissors && c2 == paper) ||                         (c1 == rock     && c2 == scissors);} Choice genMove(in int r, in int p, in int s) @safe /*@nogc*/ {    immutable x = uniform!"[]"(1, r + p + s);    if (x < s)      return Choice.rock;    if (x <= s + r) return Choice.paper;    else            return Choice.scissors;} Nullable!To maybeTo(To, From)(From x) pure nothrow @safe {    try {        return typeof(return)(x.to!To);    } catch (ConvException) {        return typeof(return)();    } catch (Exception e) {        static immutable err = new Error("std.conv.to failure");        throw err;    }} void main() /*@safe*/ {    int r = 1, p = 1, s = 1;     while (true) {        write("rock, paper or scissors? ");        immutable hs = readln.strip.toLower;        if (hs.empty)            break;         immutable h = hs.maybeTo!Choice;        if (h.isNull) {            writeln("Wrong input: ", hs);            continue;        }         immutable c = genMove(r, p, s);        writeln("Player: ", h.get, " Computer: ", c);              if (beats(h, c)) writeln("Player wins\n");        else if (beats(c, h)) writeln("Player loses\n");        else                  writeln("Draw\n");         final switch (h.get) {            case Choice.rock:     r++; break;            case Choice.paper:    p++; break;            case Choice.scissors: s++; break;        }    }}`
Output:
```rock, paper or scissors? paper
Player: paper Computer: paper
Draw

rock, paper or scissors? scissors
Player: scissors Computer: scissors
Draw

rock, paper or scissors? rock
Player: rock Computer: paper
Player loses

rock, paper or scissors? rock
Player: rock Computer: paper
Player loses

rock, paper or scissors?
```

## Elixir

Translation of: Erlang
`defmodule Rock_paper_scissors do  def play, do: loop([1,1,1])   defp loop([r,p,s]=odds) do    IO.gets("What is your move? (R,P,S,Q) ") |> String.upcase |> String.first    |> case do           "Q" -> IO.puts "Good bye!"           human when human in ["R","P","S"] ->              IO.puts "Your move is #{play_to_string(human)}."              computer = select_play(odds)              IO.puts "My move is #{play_to_string(computer)}"              case beats(human,computer) do                  true  -> IO.puts "You win!"                  false -> IO.puts "I win!"                  _     -> IO.puts "Draw"              end              case human do                  "R" -> loop([r+1,p,s])                  "P" -> loop([r,p+1,s])                  "S" -> loop([r,p,s+1])              end           _ ->              IO.puts "Invalid play"              loop(odds)       end  end   defp beats("R","S"), do: true  defp beats("P","R"), do: true  defp beats("S","P"), do: true  defp beats(x,x), do: :draw  defp beats(_,_), do: false   defp play_to_string("R"), do: "Rock"  defp play_to_string("P"), do: "Paper"  defp play_to_string("S"), do: "Scissors"   defp select_play([r,p,s]) do    n = :rand.uniform(r+p+s)    cond do        n <= r   -> "P"        n <= r+p -> "S"        true     -> "R"    end  endend Rock_paper_scissors.play`

Sample output:

```What is your move? (R,P,S,Q) r
My move is Scissors
You win!
What is your move? (R,P,S,Q) p
My move is Paper
Draw
What is your move? (R,P,S,Q) s
My move is Scissors
Draw
What is your move? (R,P,S,Q) q
Good bye!
```

## Erlang

` -module(rps).-compile(export_all). play() ->    loop([1,1,1]). loop([R,P,S]=Odds) ->    case io:fread("What is your move? (R,P,S,Q) ","~c") of        {ok,["Q"]} -> io:fwrite("Good bye!~n");        {ok,[[Human]]} when Human == \$R; Human == \$P; Human == \$S ->            io:fwrite("Your move is ~s.~n",                      [play_to_string(Human)]),            Computer = select_play(Odds),            io:fwrite("My move is ~s~n",                      [play_to_string(Computer)]),            case {beats(Human,Computer),beats(Computer,Human)} of                {true,_} -> io:fwrite("You win!~n");                {_,true} -> io:fwrite("I win!~n");                _ -> io:fwrite("Draw~n")            end,            case Human of                \$R -> loop([R+1,P,S]);                \$P -> loop([R,P+1,S]);                \$S -> loop([R,P,S+1])            end;        _ ->            io:fwrite("Invalid play~n"),            loop(Odds)    end. beats(\$R,\$S) -> true;beats(\$P,\$R) -> true;beats(\$S,\$P) -> true;beats(_,_) -> false. play_to_string(\$R) -> "Rock";play_to_string(\$P) -> "Paper";play_to_string(\$S) -> "Scissors". select_play([R,P,S]) ->    N = random:uniform(R+P+S),    if        N =< R -> \$P;        N =< R+P -> \$S;        true -> \$R    end. `

## Euphoria

Translation of: C
`function weighted_rand(sequence table)    integer sum,r    sum = 0    for i = 1 to length(table) do        sum += table[i]    end for     r = rand(sum)    for i = 1 to length(table)-1 do        r -= table[i]        if r <= 0 then            return i        end if    end for    return length(table)end function constant names = { "Rock", "Paper", "Scissors" }constant winner = { "We tied.", "Meself winned.", "You win." }integer user_action, my_action, key, winsequence user_rec, scoreuser_rec = {1,1,1}score = {0,0} while 1 do    my_action = remainder(weighted_rand(user_rec)+1,3)+1    puts(1,"Your choice [1-3]:\n")    puts(1,"  1. Rock\n  2. Paper\n  3. Scissors\n> ")    key = -1    while (key < '1' or key > '3') and key != 'q' do        key = get_key()    end while    puts(1,key)    puts(1,'\n')    if key = 'q' then        exit    end if    user_action = key-'0'    win = remainder(my_action-user_action+3,3)    printf(1,"You chose %s; I chose %s. %s\n",        { names[user_action],          names[my_action],          winner[win+1] })     if win then        score[win] += 1    end if    printf(1,"\nScore %d:%d\n",score)    user_rec[user_action] += 1end while`

## F#

`open System let random = Random ()let rand = random.NextDouble () //Gets a random number in the range (0.0, 1.0) /// Union of possible choices for a round of rock-paper-scissorstype Choice =| Rock| Paper| Scissors /// Gets the string representation of a Choicelet getString = function    | Rock -> "Rock"    | Paper -> "Paper"    | Scissors -> "Scissors" /// Defines rules for winning and losinglet beats (a : Choice, b : Choice) =    match a, b with    | Rock, Scissors -> true    // Rock beats Scissors    | Paper, Rock -> true       // Paper beats Rock    | Scissors, Paper -> true   // Scissors beat Paper    | _, _ -> false /// Generates the next move for the computer based on probability derived from previous player moves.let genMove r p s =    let tot = r + p + s    let n = rand    if n <= s / tot then Rock    elif n <= (s + r) / tot then Paper    else Scissors /// Gets the move chosen by the playerlet rec getMove () =    printf "[R]ock, [P]aper, or [S]cissors?: "    let choice = Console.ReadLine ()    match choice with    | "r" | "R" -> Rock    | "p" | "P" -> Paper    | "s" | "S" -> Scissors    | _ ->        printf "Invalid choice.\n\n"        getMove () /// Place where all the game logic takes place.let rec game (r : float, p : float, s : float) =    let comp = genMove r p s    let player = getMove ()    Console.WriteLine ("Player: {0} vs Computer: {1}", getString player, getString comp)    Console.WriteLine (        if beats(player, comp) then "Player Wins!\n"        elif beats(comp, player) then "Computer Wins!\n"        else "Draw!\n"    )    let nextR = if player = Rock then r + 1.0 else r    let nextP = if player = Paper then p + 1.0 else p    let nextS = if player = Scissors then s + 1.0 else s    game (nextR, nextP, nextS) game(1.0, 1.0, 1.0) `

## Fortran

Please find an example run in a GNU/linux system along with compilation instructions at the beginning of the FORTRAN 2008 source code. Following the source are examples demonstrating the effectiveness of the built in simple predictive artificial intelligence. It uses the yes utility for a constant data source.

` ! compilation! gfortran -std=f2008 -Wall -ffree-form -fall-intrinsics -fimplicit-none f.f08 -o f!! EXAMPLE!!\$ ./f!rock, paper, scissors?  papier!scoring computer choice (r) and your choice (p)!rock, paper, scissors?  sizzerz!scoring computer choice (s) and your choice (s)!rock, paper, scissors?  quit!scoring computer choice (r) and your choice (q)! Who's keeping score anyway???!  0.5  1.5! you won!!\$    program rpsgame   integer, parameter :: COMPUTER=1, HAPLESSUSER=2  integer, dimension(3) :: rps = (/1,1,1/)  real, dimension(3) :: p  character :: answer, cc ! computer choice  integer :: exhaustion, i  real, dimension(2) :: score = (/0, 0/)  character(len=8), dimension(3) :: choices = (/'rock    ','paper   ','scissors'/)  real :: harvest  do exhaustion = 1, 30    p = rps/real(sum(rps))    p(2) = p(2) + p(1)    p(3) = p(3) + p(2)    call random_number(harvest)    i = sum(merge(1,0,harvest.le.p)) ! In memory of Ken Iverson, logical is more useful as integer.    cc = 'rsp'(i:i)    write(6, "(2(A,', '),A,'?  ')", advance='no')(trim(choices(i)),i=1,size(choices))    read(5, *) answer    write(6, "('scoring computer choice (',A,') and your choice (',A,')')")cc,answer    if (answer.eq.cc) then      score = score + 0.5    else      i = HAPLESSUSER      if (answer.eq.'r') then        if (cc.eq.'p') i = COMPUTER      else if (answer.eq.'p') then        if (cc.eq.'s') i = COMPUTER      else if (answer.eq.'s') then        if (cc.eq.'r') i = COMPUTER      else        exit      endif      score(i) = score(i) + 1    end if    i = scan('rps',answer)    rps(i) = rps(i) + 1  end do  if (25 .lt. exhaustion) write(6, *) "I'm bored out of my skull"  write(6, *)"Who's keeping score anyway???"  write(6, '(2f5.1)') score  if (score(COMPUTER) .lt. score(HAPLESSUSER)) print*,'you won!'end program rpsgame `

rpsgame won't play more than 30 games at a time.

` \$ yes r | ./f                                                         # rockrock, paper, scissors?  scoring computer choice (r) and your choice (r)rock, paper, scissors?  scoring computer choice (s) and your choice (r)rock, paper, scissors?  scoring computer choice (r) and your choice (r)...rock, paper, scissors?  scoring computer choice (p) and your choice (r) I'm bored out of my skull Who's keeping score anyway??? 25.5  4.5yes: standard output: Broken pipeyes: write error\$ yes p 2>/dev/null | ./f                                             # paperrock, paper, scissors?  scoring computer choice (r) and your choice (p)rock, paper, scissors?  scoring computer choice (s) and your choice (p)rock, paper, scissors?  scoring computer choice (r) and your choice (p)rock, paper, scissors?  scoring computer choice (s) and your choice (p)...rock, paper, scissors?  scoring computer choice (s) and your choice (p) I'm bored out of my skull Who's keeping score anyway??? 25.5  4.5\$ yes scissors 2>/dev/null | ./f                                      # scissorsrock, paper, scissors?  scoring computer choice (r) and your choice (s)rock, paper, scissors?  scoring computer choice (r) and your choice (s)...rock, paper, scissors?  scoring computer choice (r) and your choice (s) I'm bored out of my skull Who's keeping score anyway??? 26.5  3.5\$  `

## GlovePIE

You can only press the R, P or S key to advance.

`if var.end=0 thenvar.end=0var.computerchoice=random(3) // 1 is rock, 2 is paper, and 3 is scissors.debug="Press the R key for rock, the P key for paper, or the S key for scissors:"endifif pressed(Key.R)and var.end=0 then   var.end=1   if var.computerchoice=1 then      debug="You chose rock, which the computer also chose, so it's a tie!"   else      if var.computerchoice=2 then         debug="The computer chose paper, covering your choice of rock, so you lose!"      else         debug="You chose rock, smashing the computer's choice of scissors, so you win!"      endif   endifendifif pressed(Key.P)and var.end=0 then   var.end=1   if var.computerchoice=1 then      debug="You chose paper, covering the computer's choice of rock, so you win!"   else      if var.computerchoice=2 then         debug="You chose paper, which the computer also chose, so it's a tie!"      else         debug="The computer chose scissors, cutting your choice of paper, so you lose!"      endif   endifendifif pressed(Key.S)and var.end=0 then   var.end=1   if var.computerchoice=1 then      debug="The computer chose rock, smashing your choice of scissors, so you lose!"   else      if var.computerchoice=2 then         debug="You chose scissors, cutting the computer's choice of paper, so you win!"      else         debug="You chose scissors, which the computer also chose, so it's a tie!"      endif   endifendif`

## Go

`package main import (    "fmt"    "math/rand"    "strings"    "time") const rps = "rps" var msg = []string{    "Rock breaks scissors",    "Paper covers rock",    "Scissors cut paper",} func main() {    rand.Seed(time.Now().UnixNano())    fmt.Println("Rock Paper Scissors")    fmt.Println("Enter r, p, or s as your play.  Anything else ends the game.")    fmt.Println("Running score shown as <your wins>:<my wins>")    var pi string // player input    var aScore, pScore int    sl := 3               // for output alignment    pcf := make([]int, 3) // pcf = player choice frequency    var plays int    aChoice := rand.Intn(3) // ai choice for first play is completely random    for {        // get player choice        fmt.Print("Play: ")        _, err := fmt.Scanln(&pi)  // lazy        if err != nil || len(pi) != 1 {            break        }        pChoice := strings.Index(rps, pi)        if pChoice < 0 {            break        }        pcf[pChoice]++        plays++         // show result of play        fmt.Printf("My play:%s%c.  ", strings.Repeat(" ", sl-2), rps[aChoice])        switch (aChoice - pChoice + 3) % 3 {        case 0:            fmt.Println("Tie.")        case 1:            fmt.Printf("%s.  My point.\n", msg[aChoice])            aScore++        case 2:            fmt.Printf("%s.  Your point.\n", msg[pChoice])            pScore++        }         // show score        sl, _ = fmt.Printf("%d:%d  ", pScore, aScore)         // compute ai choice for next play        switch rn := rand.Intn(plays); {        case rn < pcf[0]:            aChoice = 1        case rn < pcf[0]+pcf[1]:            aChoice = 2        default:            aChoice = 0        }    }}`
Sample output:
```Rock Paper Scissors
Enter r, p, or s as your play.  Anything else ends the game.
Running score shown as <your wins>:<my wins>
Play: r
My play: r.  Tie.
0:0  Play: p
My play:   p.  Tie.
0:0  Play: s
My play:   p.  Scissors cut paper.  Your point.
1:0  Play: r
My play:   p.  Paper covers rock.  My point.
1:1  Play: r
My play:   r.  Tie.
1:1  Play: r
My play:   p.  Paper covers rock.  My point.
1:2  Play:
```

`package main import (    "flag"    "fmt"    "log"    "math/rand"    "regexp"    "strings"    "time"     "github.com/BurntSushi/toml") var help = `rps plays rock-paper-scissors with optional addition weapons. Usage: rps [-h] [game]   -h   display help.   game is a game description file in TOML (https://github.com/mojombo/toml). The traditional game can be described as title = "Rock Paper Scissors"win = [   "rock breaks scissors",   "paper covers rock",   "scissors cut paper",] The title is optional, it just prints out at the beginning of a game. The "win" list is statments where the first word wins over the last word. It's case sensitive so make things easy by using consistent case.Don't use punctuation, at least not next to a first or last word. Additionally, you can have a "lose" key where the first word loses to thethe last, for example lose = ["rock falls into well"] To organize things with additional weapons, you can just use the winningweapon with a list of clauses, for example lizard = ["poisons Spock", "eats paper"] The progam ignores anything in parentheses when identifying first or lastwords.  Examples (from RPS-101) with weapons gun, fire, and sword, win = [   "gun fire(s)"   "(flaming) sword has fire"] Finally, TOML is a hash, so don't duplicate keys.  That means no multiplewin or lose keys.  You must combine all the win statements and all the losestatements.` var rps = `title = "Rock Paper Scissors"win = [    "rock breaks scissors",    "paper covers rock",    "scissors cut paper",]` func main() {    h := flag.Bool("h", false, "show help")    flag.Parse()    if *h {        fmt.Println(help)        return    }    m := map[string]interface{}{}    var err error    switch flag.NArg() {    case 0:        _, err = toml.Decode(rps, &m)    case 1:        _, err = toml.DecodeFile(flag.Arg(0), &m)    default:        flag.Usage()        return    }    if err != nil {        log.Fatal(err)    }    play(parse(m))} type decision map[string]map[string]string type fIndex map[string]int func parse(m map[string]interface{}) (title string, f fIndex, d decision) {    d = decision{}    for k, v := range m {        switch t := v.(type) {        case []interface{}:            d.parseList(k, t)        case string:            if k == "title" {                title = t            } else {                log.Println("Unknown key:", k)            }        }    }    i := 0    f = fIndex{}    for w, wl := range d {        if _, ok := f[w]; !ok {            f[w] = i            i++        }        for l := range wl {            if _, ok := f[l]; !ok {                f[l] = i                i++            }        }    }    for fm := range f {         if _, ok := d[fm]; !ok {            log.Println("note,", fm, "always loses!")        }    }    balanced := len(f)&1 == 1    for _, l := range d {        if !balanced {            break        }        balanced = len(l)*2+1 == len(f)    }    if !balanced {        log.Print("note, game is unbalanced")    }    return title, f, d}    var r = regexp.MustCompile(`[(].*[)]`) func (d decision) parseList(kw string, l []interface{}) {    var ww string    for _, e := range l {        st, ok := e.(string)        if !ok {            log.Fatal("invalid", e)        }        w := strings.Fields(r.ReplaceAllLiteralString(st, ""))        if len(w) == 0 {            log.Fatalln("invalid:", kw, st)        }        lw := w[len(w)-1]        switch kw {        case "win":            ww = w[0]        case "lose":            ww, lw = lw, w[0]        default:            ww = kw            for i := 0; ; i++ {                if i == len(w) {                    st = ww + " " + st                    break                }                if w[i] == ww {                    break                }            }        }        if lw == ww {            log.Fatalln("invalid:", st)        }        if cs, ok := d[lw][ww]; ok {            log.Fatalln("conflict:", cs, "and", st)        }        d1, ok := d[ww]        if !ok {            d1 = map[string]string{}        }        d1[lw] = st        d[ww] = d1    }} func play(title string, fx fIndex, d decision) {    rand.Seed(time.Now().Unix())    if len(fx) == 0 {        return    }    form := make([]string, len(fx))    for w, i := range fx {        form[i] = w    }    fmt.Println()    fmt.Println(title)    fmt.Print("Choices are ", form[0])    for _, w := range form[1:] {        fmt.Printf(", %s", w)    }    fmt.Println(".")    fmt.Println("Enter one of these choices as your play.  " +        "Anything else ends the game.")    fmt.Println("Running score shown as <your wins>:<my wins>")    var pw string    var aScore, pScore int    sl := 3    wcf := make([]int, len(form))    wct := 0    ax := rand.Intn(len(form))    aw := form[ax]    for {        fmt.Print("Play: ")        _, err := fmt.Scanln(&pw)        if err != nil {            break        }        px, ok := fx[pw]        if !ok {            fmt.Println(pw, "invalid.")            break        }        for f, l := range d {            if _, ok := l[pw]; ok {                wcf[fx[f]]++                wct++            }        }         fmt.Printf("My play:%s%s.\n", strings.Repeat(" ", sl-2), aw)        ast := d[aw][pw]        pst := d[pw][aw]        switch {        case ax == px:            fmt.Println("Tie.")        case ast > "" && pst > "":            log.Fatalln("conflict: ", ast, "and", pst)        case ast > "":            fmt.Printf("%s.  My point.\n", ast)            aScore++        default:            fmt.Printf("%s.  Your point.\n", pst)            pScore++        }        sl, _ = fmt.Printf("%d:%d  ", pScore, aScore)        ax = 0        for rn := rand.Intn(wct); ; ax++ {            if f := wcf[ax]; rn < f {                break            } else {                rn -= f            }        }        aw = form[ax]    }}`

Example game files:

```# example unbalanced game described with both win and lose statements

title = "Rock Paper Scissors Well"
win = [
"rock breaks scissors",
"paper covers rock",
"paper covers well",
"scissors cut paper",
]
lose = [
"rock falls into well",
"scissors fall into well",
]
```
```# example with implied wins, parenthetical word.

title = "RPS-7"
rock = [
"pounds out fire",
"crushes scissors",
"crushes sponge",
]
fire = [
"melts scissors",
"burns paper",
"burns sponge",
]
scissors = [
"swish through air",
"cut paper",
"cut sponge",
]
sponge = [
"soaks paper",
"uses air (pockets)",
"absorbs water",
]
paper = [
"fans air",
"covers rock",
"floats on water",
]
air = [
"blows out fire",
"erodes rock",
"evaporates water",
]
water = [
"erodes rock",
"puts out fire",
"rusts scissors",
]
```
Example output:
```> rps rpsw
2014/05/20 20:42:03 note, game is unbalanced

Rock Paper Scissors Well
Choices are rock, scissors, paper, well.
Enter one of these choices as your play.  Anything else ends the game.
Running score shown as <your wins>:<my wins>
Play: rock
My play: rock.
Tie.
0:0  Play: well
My play:   paper.
paper covers well.  My point.
0:1  Play: scissors
My play:   paper.
1:1  Play: well
My play:   paper.
paper covers well.  My point.
1:2  Play:

> rps rps7

RPS-7
Choices are rock, scissors, sponge, fire, paper, air, water.
Enter one of these choices as your play.  Anything else ends the game.
Running score shown as <your wins>:<my wins>
Play: air
My play: water.
1:0  Play:
```

`import System.Random (randomRIO) data Choice  = Rock  | Paper  | Scissors  deriving (Show, Eq) beats :: Choice -> Choice -> Boolbeats Paper Rock = Truebeats Scissors Paper = Truebeats Rock Scissors = Truebeats _ _ = False genrps :: (Int, Int, Int) -> IO Choicegenrps (r, p, s) = rps <\$> rand  where    rps x      | x <= s = Rock      | x <= s + r = Paper      | otherwise = Scissors    rand = randomRIO (1, r + p + s) :: IO Int getrps :: IO Choicegetrps = rps <\$> getLine  where    rps "scissors" = Scissors    rps "rock" = Rock    rps "paper" = Paper    rps _ = error "invalid input" game :: (Int, Int, Int) -> IO agame (r, p, s) = do  putStrLn "rock, paper or scissors?"  h <- getrps  c <- genrps (r, p, s)  putStrLn ("Player: " ++ show h ++ " Computer: " ++ show c)  putStrLn    (if beats h c       then "player wins\n"       else if beats c h              then "player loses\n"              else "draw\n")  let rr =        if h == Rock          then r + 1          else r      pp =        if h == Paper          then p + 1          else p      ss =        if h == Scissors          then s + 1          else s  game (rr, pp, ss) main :: IO amain = game (1, 1, 1)`

## Icon and Unicon

The key to this comes down to two structures and two lines of code. The player history historyP is just an ordered list of every player turn and provides the weight for the random selection. The beats list is used to rank moves and to choose the move that would beat the randomly selected move.

`link printf procedure main() printf("Welcome to Rock, Paper, Scissors.\n_        Rock beats scissors, Scissors beat paper, and Paper beats rock.\n\n") historyP := ["rock","paper","scissors"]      # seed player history  winP := winC := draws := 0                   # totals beats := ["rock","scissors","paper","rock"]  # what beats what 1 apart repeat {   printf("Enter your choice or rock(r), paper(p), scissors(s) or quit(q):")   turnP := case map(read()) of {      "q"|"quit": break      "r"|"rock": "rock"      "p"|"paper": "paper"      "s"|"scissors": "scissors"      default:  printf(" - invalid choice.\n") & next      }    turnC := beats[(?historyP == beats[i := 2 to *beats],i-1)]  # choose move    put(historyP,turnP)                       # record history   printf("You chose %s, computer chose %s",turnP,turnC)       (beats[p := 1 to *beats] == turnP) &       (beats[c := 1 to *beats] == turnC) & (abs(p-c) <= 1)  # rank play    if p = c then      printf(" - draw (#%d)\n",draws +:= 1 )   else if p > c then         printf(" - player win(#%d)\n",winP +:= 1)           else       printf(" - computer win(#%d)\n",winC +:= 1)       } printf("\nResults:\n %d rounds\n %d Draws\n %d Computer wins\n %d Player wins\n",   winP+winC+draws,draws,winC,winP)   end`
Sample output:
```Welcome to Rock, Paper, Scissors.
Rock beats scissors, Scissors beat paper, and Paper beats rock.

Enter your choice or rock(r), paper(p), scissors(s) or quit(q):s
You chose scissors, computer chose scissors - draw (#1)
Enter your choice or rock(r), paper(p), scissors(s) or quit(q):p
You chose paper, computer chose paper - draw (#2)
Enter your choice or rock(r), paper(p), scissors(s) or quit(q):r
You chose rock, computer chose scissors - computer win(#1)
Enter your choice or rock(r), paper(p), scissors(s) or quit(q):r
You chose rock, computer chose rock - draw (#3)
Enter your choice or rock(r), paper(p), scissors(s) or quit(q):p
You chose paper, computer chose paper - draw (#4)
Enter your choice or rock(r), paper(p), scissors(s) or quit(q):s
You chose scissors, computer chose scissors - draw (#5)
Enter your choice or rock(r), paper(p), scissors(s) or quit(q):r
You chose rock, computer chose rock - draw (#6)
Enter your choice or rock(r), paper(p), scissors(s) or quit(q):r
You chose rock, computer chose paper - player win(#1)
Enter your choice or rock(r), paper(p), scissors(s) or quit(q):q

Results:
8 rounds
6 Draws
1 Computer wins
1 Player wins```

## IS-BASIC

`100 PROGRAM "Rock.bas"110 RANDOMIZE120 STRING CH\$(1 TO 3)*8,K\$*1130 NUMERIC PLWINS(1 TO 3),SCORE(1 TO 3),PLSTAT(1 TO 3),CMSTAT(1 TO 3),PLCHOICE,CMCHOICE140 CALL INIC150 DO160   CALL GUESS170   PRINT :PRINT "Rock, paper, or scissors (1 = rock, 2 = paper, 3 = scissors, ESC = quit)"180   DO190     LET K\$=INKEY\$200   LOOP UNTIL K\$>="1" AND K\$<="3" OR K\$=CHR\$(27)210   IF K\$=CHR\$(27) THEN EXIT DO220   LET PLCHOICE=VAL(K\$)230   LET CMSTAT(CMCHOICE)=CMSTAT(CMCHOICE)+1:LET PLSTAT(PLCHOICE)=PLSTAT(PLCHOICE)+1240   PRINT "You chose ";CH\$(PLCHOICE);" and I chose ";CH\$(CMCHOICE);"."250   SET #102:INK 3260   IF PLCHOICE=CMCHOICE THEN270     PRINT "Tie!"280     LET SCORE(3)=SCORE(3)+1290   ELSE IF CMCHOICE=PLWINS(PLCHOICE) THEN300     PRINT "You won!"310     LET SCORE(1)=SCORE(1)+1320   ELSE330     PRINT "I won!"340     LET SCORE(2)=SCORE(2)+1350   END IF 360   SET #102:INK 1370 LOOP380 PRINT :PRINT "Some useless statistics:"390 PRINT "You won";SCORE(1);"times, and I won";SCORE(2);"times;";SCORE(3);"ties."400 PRINT :PRINT ,,CH\$(1),CH\$(2),CH\$(3)410 PRINT "You chose:",PLSTAT(1),PLSTAT(2),PLSTAT(3)420 PRINT "  I chose:",CMSTAT(1),CMSTAT(2),CMSTAT(3)430 END440 DEF INIC450   LET CH\$(1)="rock":LET CH\$(2)="paper":LET CH\$(3)="scissors"460   LET PLWINS(1)=3:LET PLWINS(2)=1:LET PLWINS(3)=2470   FOR I=1 TO 3480     LET PLSTAT(I),CMSTAT(I),SCORE(I)=0490   NEXT500   TEXT 80510 END DEF520 DEF GUESS530   LET CMCHOICE=INT(RND*(PLSTAT(1)+PLSTAT(2)+PLSTAT(3)+3))540   SELECT CASE CMCHOICE550   CASE 0 TO PLSTAT(1)560     LET CMCHOICE=2570   CASE PLSTAT(1)+1 TO PLSTAT(1)+PLSTAT(2)+1580     LET CMCHOICE=3590   CASE ELSE600     LET CMCHOICE=1610   END SELECT620 END DEF`

## J

`require'general/misc/prompt strings' NB. was 'misc strings' in older versions of Jgame=:3 :0  outcomes=. rps=. 0 0 0  choice=. 1+?3  while.#response=. prompt'  Choose Rock, Paper or Scissors: ' do.    playerchoice=. 1+'rps' i. tolower {.deb response    if.4 = playerchoice do.      smoutput 'Unknown response.'      smoutput 'Enter an empty line to quit'      continue.    end.    smoutput '    I choose ',choice {::;:'. Rock Paper Scissors'    smoutput (wintype=. 3 | choice-playerchoice) {:: 'Draw';'I win';'You win'    outcomes=. outcomes+0 1 2 = wintype    rps=. rps+1 2 3=playerchoice    choice=. 1+3|(?0) I.~ (}:%{:)+/\ 0, rps  end.  ('Draws:','My wins:',:'Your wins: '),.":,.outcomes)`

Example use (playing to give the computer implementation the advantage):

`   game''  Choose Rock, Paper or Scissors: rock    I choose ScissorsYou win  Choose Rock, Paper or Scissors: rock    I choose PaperI win  Choose Rock, Paper or Scissors: rock    I choose PaperI win  Choose Rock, Paper or Scissors: rock    I choose PaperI win  Choose Rock, Paper or Scissors: rock    I choose PaperI win  Choose Rock, Paper or Scissors: Draws:     0My wins:   4Your wins: 1`

## Java

Works with: Java version 1.5+

This could probably be made simpler, but some more complexity is necessary so that other items besides rock, paper, and scissors can be added (as school children and nerds like to do [setup for rock-paper-scissors-lizard-spock is in multi-line comments]). The method `getAIChoice()` borrows from the Ada example in spirit, but is more generic to additional items.

`import java.util.Arrays;import java.util.EnumMap;import java.util.List;import java.util.Map;import java.util.Scanner;import java.util.Random; public class RPS {	public enum Item{		ROCK, PAPER, SCISSORS, /*LIZARD, SPOCK*/;		public List<Item> losesToList;		public boolean losesTo(Item other) {			return losesToList.contains(other);		}		static {			SCISSORS.losesToList = Arrays.asList(ROCK/*, SPOCK*/);			ROCK.losesToList = Arrays.asList(PAPER/*, SPOCK*/);			PAPER.losesToList = Arrays.asList(SCISSORS/*, LIZARD*/);			/*			SPOCK.losesToList = Arrays.asList(PAPER, LIZARD);			LIZARD.losesToList = Arrays.asList(SCISSORS, ROCK);			*/                }	}	//EnumMap uses a simple array under the hood	public final Map<Item, Integer> counts = new EnumMap<Item, Integer>(Item.class){{		for(Item item:Item.values())			put(item, 1);	}}; 	private int totalThrows = Item.values().length; 	public static void main(String[] args){		RPS rps = new RPS();		rps.run();	} 	public void run() {		Scanner in = new Scanner(System.in);		System.out.print("Make your choice: ");		while(in.hasNextLine()){			Item aiChoice = getAIChoice();			String input = in.nextLine();			Item choice;			try{				choice = Item.valueOf(input.toUpperCase());			}catch (IllegalArgumentException ex){				System.out.println("Invalid choice");				continue;			}			counts.put(choice, counts.get(choice) + 1);			totalThrows++;			System.out.println("Computer chose: " + aiChoice);			if(aiChoice == choice){				System.out.println("Tie!");			}else if(aiChoice.losesTo(choice)){				System.out.println("You chose...wisely. You win!");			}else{				System.out.println("You chose...poorly. You lose!");			}			System.out.print("Make your choice: ");		}	} 	private static final Random rng = new Random();	private Item getAIChoice() {		int rand = rng.nextInt(totalThrows);		for(Map.Entry<Item, Integer> entry:counts.entrySet()){			Item item = entry.getKey();			int count = entry.getValue();			if(rand < count){				List<Item> losesTo = item.losesToList;				return losesTo.get(rng.nextInt(losesTo.size()));			}			rand -= count;		}		return null;	}}`

Sample output:

```Make your choice: rock
Computer chose: PAPER
You chose...poorly. You lose!
Computer chose: SCISSORS
You chose...wisely. You win!
Computer chose: PAPER
You chose...poorly. You lose!
Computer chose: SCISSORS
You chose...wisely. You win!
Computer chose: PAPER
You chose...poorly. You lose!
Computer chose: ROCK
Tie!
Computer chose: ROCK
Tie!
Computer chose: PAPER
You chose...poorly. You lose!
Computer chose: PAPER
You chose...poorly. You lose!
Computer chose: PAPER
You chose...poorly. You lose!
Computer chose: PAPER
You chose...wisely. You win!
Computer chose: PAPER
You chose...wisely. You win!
...```

## Julia

`function rps()	print("Welcome to Rock, paper, scissors! Go ahead and type your pick.\n		r(ock), p(aper), or s(cissors)\n		Enter 'q' to quit.\n>")	comp_score = 0	user_score = 0	options = ["r","p","s"]	new_pick() = options[rand(1:3)]	i_win(m,y) = ((m == "r" && y == "s")|(m == "s" && y == "p")|(m == "p" && y == "r"))	while true		input = string(readline(STDIN)[1])		input == "q" && break		!ismatch(r"^[rps]",input) && begin print("Invalid guess: Please enter 'r', 'p', or 's'\n"); continue end		answer = new_pick()		if input == answer 			print("\nTie!\nScore still: \nyou \$user_score\nme  \$comp_score\n>")			continue		else			i_win(answer,input) ? (comp_score += 1) : (user_score += 1)			print(i_win(answer,input) ? "\nSorry you lose!\n" : "\nYou win!","Score: \nyou \$user_score\nme  \$comp_score\n>")		end	endend`
```julia> rps()

r(ock), p(aper), or s(cissors)

Enter 'q' to quit.
>r

You win!Score:
you 1
me  0
>p

Sorry you lose!
Score:
you 1
me  1
>s

You win!Score:
you 2
me  1```

## Kotlin

`// version 1.2.10 import java.util.Random const val choices = "rpsq"val rand = Random() var pWins = 0                  // player winsvar cWins = 0                  // computer winsvar draws = 0                  // neither winsvar games = 0                  // games playedval pFreqs = arrayOf(0, 0, 0)  // player frequencies for each choice (rps) fun printScore() = println("Wins: You \$pWins, Computer \$cWins, Neither \$draws\n") fun getComputerChoice(): Char {    // make a completely random choice until 3 games have been played    if (games < 3) return choices[rand.nextInt(3)]    val num = rand.nextInt(games)    return when {        num < pFreqs[0] -> 'p'        num < pFreqs[0] + pFreqs[1] -> 's'        else -> 'r'    }} fun main(args: Array<String>) {    println("Enter: (r)ock, (p)aper, (s)cissors or (q)uit\n")    while (true) {        printScore()        var pChoice: Char        while (true) {            print("Your choice r/p/s/q : ")            val input = readLine()!!.toLowerCase()            if (input.length == 1) {                pChoice = input[0]                if (pChoice in choices) break            }            println("Invalid choice, try again")        }        if (pChoice == 'q') {            println("OK, quitting")            return        }        val cChoice = getComputerChoice()        println("Computer's choice   : \$cChoice")        if (pChoice == 'r' && cChoice == 's') {            println("Rock breaks scissors - You win!")            pWins++        }        else if (pChoice == 'p' && cChoice == 'r') {            println("Paper covers rock - You win!")            pWins++        }        else if (pChoice == 's' && cChoice == 'p') {            println("Scissors cut paper - You win!")            pWins++        }        else if (pChoice == 's' && cChoice == 'r') {            println("Rock breaks scissors - Computer wins!")            cWins++        }        else if (pChoice == 'r' && cChoice == 'p') {            println("Paper covers rock - Computer wins!")            cWins++        }        else if (pChoice == 'p' && cChoice == 's') {            println("Scissors cut paper - Computer wins!")            cWins++        }        else {            println("It's a draw!")            draws++        }        pFreqs[choices.indexOf(pChoice)]++        games++        println()    }}`

Sample session:

```Enter: (r)ock, (p)aper, (s)cissors or (q)uit

Wins: You 0, Computer 0, Neither 0

Computer's choice   : r
It's a draw!

Wins: You 0, Computer 0, Neither 1

Computer's choice   : s
Scissors cut paper - Computer wins!

Wins: You 0, Computer 1, Neither 1

Computer's choice   : r
Paper covers rock - You win!

Wins: You 1, Computer 1, Neither 1

Computer's choice   : s
It's a draw!

Wins: You 1, Computer 1, Neither 2

Computer's choice   : p
It's a draw!

Wins: You 1, Computer 1, Neither 3

OK, quitting
```

## Lasso

Notes: This implementation uses the default session handling in Lasso, and assumes it's running on a web server. User choices are passed in via HTTP as GET query parameters.

`session_start('user')session_addvar('user', 'historic_choices')session_addvar('user', 'win_record')session_addvar('user', 'plays')var(historic_choices)->isNotA(::map) ? var(historic_choices = map('rock'=0, 'paper'=0, 'scissors'=0))var(plays)->isNotA(::integer) ? var(plays = 0)var(win_record)->isNotA(::array) ? var(win_record = array) define br => '<br>'define winner(c::string,p::string) => {	if(#c == \$superior->find(#p)) => {		\$win_record->insert('lasso')		return 'Lasso'	else(#p == \$superior->find(#c))		\$win_record->insert('user')		return 'User'	else		\$win_record->insert('tie')		return 'Nobody'		}	} 	var(		choice 				= web_request->param('choice')->asString,	lookup 				= array('rock', 'paper', 'scissors'),	computer_choice 	= \$lookup->get(math_random(3,1)),	superior			= map('rock'='paper', 'paper'='scissors', 'scissors'='rock'),	controls			= '<a href=?choice=rock>Rock</a> <a href=?choice=paper>Paper</a> <a href=?choice=scissors>Scissors</a> <a href=?choice=quit>Quit</a><br/>')if(\$choice == 'quit') => {^	'See ya. <a href=?>Start over</a>'	session_end('user')	\$historic_choices = map('rock'=0, 'paper'=0, 'scissors'=0)	\$plays = 0	\$win_record = array else(array('rock','paper','scissors') >> \$choice)		\$controls 		if(\$plays != 0) => {			local('possibilities') = array			with i in \$lookup do => {				loop(\$historic_choices->find(#i)) => { #possibilities->insert(#i) }			} 			\$computer_choice = \$superior->find(#possibilities->get(math_random(\$plays,1)))		} 		'User chose ' + \$choice + br	'Lasso chose ' + \$computer_choice + br	winner(\$computer_choice->asString, \$choice) + ' wins!' 		\$historic_choices->find(\$choice) = \$historic_choices->find(\$choice)+1		\$plays += 1 	else(\$choice->size == 0)		\$controls 	else		'Invalid Choice.'+ br + \$controls^}if(\$win_record->size) => {^	br	br	'Win record: '+br	'Lasso: '+(\$win_record->find('lasso')->size)+br	'User: '+(\$win_record->find('user')->size)+br	'Tie: '+(\$win_record->find('tie')->size)+br^}`
Output:
```Rock Paper Scissors Quit (<- as links)
User chose paper
Lasso chose rock
User wins!

Win record:
Lasso: 2
User: 1
Tie: 3```

## Liberty BASIC

` dim rps( 2), g\$( 3) g\$( 0) ="rock": g\$( 1) ="paper": g\$( 2) ="scissors"global total total =0: draw  =0: pwin  =0: cwin  =0 rps( 0) =1: rps( 1) =1: rps( 2) =1          '   at first computer will play all three with equal probability c =int( 3 *rnd( 1))                         '   first time, computer response is random '   In the following code we set three integer %ages for the <human>'s biassed throws.                                            '   set up the <human> player's key frequencies as %ages.                                            '   Done like this it's easy to mimic the <human> input of q\$                                            '   It allows only integer %age frequency- not an important thing.rockP =45                                   '   <<<<<<<<< Set here the <human>'s %age of 'rock' choices.for i =1 to rockP: qF\$ =qF\$ +"R": next i paprP =24                                    '   <<<<<<<<< Set here the %age of 'paper' choices.for i =1 to paprP: qF\$ =qF\$ +"P": next i scisP =100 -rockP -paprP                    '   <<<<<<<<< %age 'scissors' calculated to make 100%for i =1 to scisP: qF\$ =qF\$ +"S": next i'print qF\$ do  'do: input q\$:loop until instr( "RPSrpsQq", q\$)   '   for actual human input... possibly biassed.         <<<<<<<<<<<<< REM one or the other line...  q\$ =mid\$( qF\$, int( 100 *rnd( 1)), 1)              '   simulated <human> input with controlled bias.      <<<<<<<<<<<<<   if total >10000 then q\$ ="Q"   g =int( ( instr( "RrPpSsQq", q\$) -1) / 2)  if g >2 then [endGame]   total    =total   +1  rps( g)  =rps( g) +1  '   accumulate plays the <human> has chosen. ( & hence their (biassed?) frequencies.)  'print "  You chose "; g\$( g); " and I chose "; g\$( c); ". "   select case g -c    case 0      draw =draw +1  ':print "It's a draw"    case 1, -2      pwin =pwin +1  ':print "You win!"    case -1, 2      cwin =cwin +1  ':print "I win!"   end select    r =int( total *rnd( 1))      '   Now select computer's choice for next confrontation.   select case                  '   Using the accumulating data about <human>'s frequencies so far.        case r <=rps( 0)            c =1        case r <=( rps( 0) +rps( 1))            c =2        case else            c =0   end select    scanloop until 0 [endGame]    print    print "  You won "; pwin; ", and I won "; cwin; ". There were "; draw; " draws."    if cwin >pwin then print "      I AM THE CHAMPION!!" else print "        You won this time."    print    print "  At first I assumed you'd throw each equally often."    print "  This means I'd win 1 time in 3; draw 1 in 3; lose 1 in 3."    print "  However if I detect a bias in your throws,...."    print "  ....this allows me to anticipate your most likely throw & on average beat it."    print    print "  In fact, keyboard layout & human frailty mean even if you TRY to be even & random..."    print "  ... you may be typing replies with large bias. In 100 tries I gave 48 'P's, 29 'R' & 23 'S'!"    print    print "    This time I played.."    print "      Rock "; using( "##.##", rps( 2)* 100 /total); "%    Paper "; using( "##.##", rps( 0) *100 /total); "%    Scissors "; using( "##.##", rps( 1) *100 /total); "%."    print    print "  ( PS. I have since learned your actual bias had been.."    print "      Rock "; using( "##.##", rockP); "%    Paper "; using( "##.##", paprP ); "%    Scissors "; using( "##.##", ( 100 -rockP -paprP)); "%.)"    print    print "  The advantage I can gain gets bigger the further the 'human' entries are biassed."    print "  The results statistically smooth out better with large runs."    print "  Try 10,000,000, & have a cuppa while you wait."    print    print "  Can you see what will happen if, say, the 'human' is set to give 'Rock' EVERY time?"    print "  Try different %ages by altering the marked code lines."    print    print "  Thanks for playing!"    end `
``` You won 3204, and I won 3669. There were 3128 draws.
I AM THE CHAMPION!!

At first I assumed you'd throw each equally often.
This means I'd win 1 time in 3; draw 1 in 3; lose 1 in 3.
However if I detect a bias in your throws,....
....this allows me to anticipate your most likely throw & on average beat it.

In fact, keyboard layout & human frailty mean even if you TRY to be even & random...
... you may be typing replies with large bias. In 100 tries I gave 48 'P's, 29 'R' & 23 'S'!

This time I played..
Rock 30.17%    Paper 45.93%    Scissors 23.94%.

Rock 45.00%    Paper 24.00%    Scissors 31.00%.)

The advantage I can gain gets bigger the further the 'human' entries are biassed.
The results statistically smooth out better with large runs.
Try 10,000,000, & have a cuppa while you wait.

Can you see what will happen if, say, the 'human' is set to give 'Rock' EVERY time?
Try different %ages by altering the marked code lines.
```

## Locomotive Basic

Translation of: Go
`10 mode 1:defint a-z:randomize time20 rps\$="rps"30 msg\$(1)="Rock breaks scissors"40 msg\$(2)="Paper covers rock"50 msg\$(3)="Scissors cut paper"60 print "Rock Paper Scissors":print70 print "Enter r, p, or s as your play."80 print "Running score shown as <your wins>:<my wins>"90 achoice=rnd*2.99+.5 ' get integer between 1 and 3 from real between .5 and <3.5100 ' get key110 pin\$=inkey\$120 if pin\$="" then 110130 pchoice=instr(rps\$,pin\$)140 if pchoice=0 then print "Sorry?":goto 110150 pcf(pchoice)=pcf(pchoice)+1160 plays=plays+1170 print "My play: "mid\$(rps\$,achoice,1)180 sw=(achoice-pchoice+3) mod 3190 if sw=0 then print "Tie." else if sw=1 then print msg\$(achoice);". My point.":ascore=ascore+1 else print msg\$(pchoice);". Your point.":pscore=pscore+1200 print pscore":"ascore210 rn=rnd*plays220 if rn<pcf(1) then achoice=2 else if rn<pcf(1)+pcf(2) then achoice=3 else achoice=1230 goto 110`

## Lua

`function cpuMove()    local totalChance = record.R + record.P + record.S  if totalChance == 0 then  -- First game, unweighted random    local choice = math.random(1, 3)    if choice == 1 then return "R" end    if choice == 2 then return "P" end    if choice == 3 then return "S" end  end  local choice = math.random(1, totalChance)  -- Weighted random bit  if choice <= record.R then return "P" end  if choice <= record.R + record.P then return "S" end  return "R"end function playerMove()  -- Get user input for choice of 'weapon'  local choice  repeat    os.execute("cls")  -- Windows specific command, change per OS    print("\nRock, Paper, Scissors")    print("=====================\n")    print("Scores -\tPlayer:", score.player)    print("\t\tCPU:", score.cpu .. "\n\t\tDraws:", score.draws)    io.write("\nChoose [R]ock [P]aper or [S]cissors: ")    choice = io.read():upper():sub(1, 1)  until choice == "R" or choice == "P" or choice == "S"  return choiceend -- Decide who won, increment scoresfunction checkWinner (c, p)  io.write("I chose ")  if c == "R" then print("rock...") end  if c == "P" then print("paper...") end  if c == "S" then print("scissors...") end  if c == p then    print("\nDraw!")    score.draws = score.draws + 1  elseif  (c == "R" and p == "P") or      (c == "P" and p == "S") or      (c == "S" and p == "R") then        print("\nYou win!")        score.player = score.player + 1  else    print("\nYou lose!")    score.cpu = score.cpu + 1  endend -- Main proceduremath.randomseed(os.time())score = {player = 0, cpu = 0, draws = 0}record = {R = 0, P = 0, S = 0}local playerChoice, cpuChoicerepeat  cpuChoice = cpuMove()  playerChoice = playerMove()  record[playerChoice] = record[playerChoice] + 1  checkWinner(cpuChoice, playerChoice)  io.write("\nPress ENTER to continue or enter 'Q' to quit . . . ")until io.read():upper():sub(1, 1) == "Q"`

Session in which I chose nothing but rock:

```Rock, Paper, Scissors
=====================

Scores -        Player: 1
CPU:    25
Draws:  0

Choose [R]ock [P]aper or [S]cissors: r
I chose paper...

You lose!

Press ENTER to continue or enter 'Q' to quit . . .
```

## Mathematica

`DynamicModule[{record, play, text = "\nRock-paper-scissors\n",   choices = {"Rock", "Paper", "Scissors"}},  Evaluate[record /@ choices] = {1, 1, 1};  play[x_] :=   Module[{y = RandomChoice[record /@ choices -> [email protected]]},    record[x]++;    text = "Your Choice:" <> x <> "\nComputer's Choice:" <> y <> "\n" <>      Switch[{x, y}, Alternatives @@ Partition[choices, 2, 1, 1],       "You lost.",       Alternatives @@ Reverse /@ Partition[choices, 2, 1, 1],       "You win.", _, "Draw."]];  [email protected]{Dynamic[text], ButtonBar[# :> play[#] & /@ choices]}]`

## OCaml

` let pf = Printf.printf ;; let looses a b = match a, b with     `R, `P -> true   | `P, `S -> true   | `S, `R -> true   |  _,  _ -> false ;; let rec get_move () =   pf "[R]ock, [P]aper, [S]cisors [Q]uit? " ;   match String.uppercase (read_line ()) with        "P" -> `P      | "S" -> `S      | "R" -> `R      | "Q" -> exit 0      | _   -> get_move () ;; let str_of_move = function        `P -> "paper"      | `R -> "rock"      | `S -> "scisors" ;; let comp_move r p s =   let tot = r +. p +. s in   let n = Random.float 1.0 in   if n < r /. tot then      `R   else      if n < (r +. p) /. tot then         `P      else         `S ;; let rec make_moves r p s =   let cm = comp_move r p s in   (* Computer move is based on game history. *)   let hm = get_move () in       (* Human move is requested. *)   pf "Me: %s. You: %s. " (str_of_move cm) (str_of_move hm);   let outcome =       if looses hm cm then         "I win. You loose.\n"      else if cm = hm then         "We draw.\n"      else          "You win. I loose.\n"   in pf "%s" outcome;   match hm with (* Play on with adapted strategy. *)        `S -> make_moves (r +. 1.) p s      | `R -> make_moves r (p +. 1.) s      | `P -> make_moves r p (s +. 1.) ;; (* Main loop. *)make_moves 1. 1. 1. ;;  `

## PARI/GP

`contest(rounds)={  my(v=[1,1,1],wins,losses); \\ Laplace rule  for(i=1,rounds,    my(computer,player,t);    t=random(v[1]+v[2]+v[3]);    if(t<v[1], computer = "R",      if(t<v[1]+v[2], computer = "P", computer = "S")    );    print("Rock, paper, or scissors?");    t = Str(input());    if(#t,      player=Vec(t)[1];      if(player <> "R" && player <> "P", player = "S")    ,      player = "S"    );    if (player == "R", v[2]++);    if (player == "P", v[3]++);    if (player == "S", v[1]++);    print1(player" vs. "computer": ");    if (computer <> player,      if((computer == "R" && player = "P") || (computer == "P" && player = "S") || (computer == "S" && player == "R"),        print("You win");        losses++      ,        print("I win");        wins++      )    ,      print("Tie");    )  );  [wins,losses]};contest(10)`

## Perl

The program supports "--quiet" option, which makes it suppress all in-game output (useful for batch testing). At the end of a game it displays detailed statistics.

` use 5.012;use warnings;use utf8;use open qw(:encoding(utf-8) :std);use Getopt::Long; package Game {    use List::Util qw(shuffle first);     my \$turns        = 0;    my %human_choice = ( rock => 0, paper => 0, scissors => 0, );    my %comp_choice  = ( rock => 0, paper => 0, scissors => 0, );    my %what_beats =      ( rock => 'paper', paper => 'scissors', scissors => 'rock', );    my \$comp_wins  = 0;    my \$human_wins = 0;    my \$draws      = 0;     sub save_human_choice {        my \$ch = lc pop;        if ( exists \$human_choice{ \$ch } ) {            ++\$human_choice{ \$ch };        }        else {            die __PACKAGE__ . ":: wrong choice: '\$ch'";        }    }     sub get_comp_choice {        my @keys = shuffle keys %human_choice;        my \$ch;        my ( \$prob, \$rand ) = ( 0, rand );        \$ch = ( first { \$rand <= ( \$prob += ( \$human_choice{ \$_ } / \$turns ) ) } @keys )            if \$turns > 0;        \$ch //= \$keys[0];        \$ch = \$what_beats{ \$ch };        ++\$comp_choice{ \$ch };        return \$ch;    }     sub make_turn {        my ( \$comp_ch, \$human_ch ) = ( pop(), pop() );        ++\$turns;        if ( \$what_beats{ \$human_ch } eq \$comp_ch ) {            ++\$comp_wins;            return 'I win!';        }        elsif ( \$what_beats{ \$comp_ch } eq \$human_ch ) {            ++\$human_wins;            return 'You win!';        }        else {            ++\$draws;            return 'Draw!';        }    }     sub get_final_report {        my \$report =            "You chose:\n"          . "  rock     = \$human_choice{rock} times,\n"          . "  paper    = \$human_choice{paper} times,\n"          . "  scissors = \$human_choice{scissors} times,\n"          . "I chose:\n"          . "  rock     = \$comp_choice{rock} times,\n"          . "  paper    = \$comp_choice{paper} times,\n"          . "  scissors = \$comp_choice{scissors} times,\n"          . "Turns: \$turns\n"          . "I won: \$comp_wins, you won: \$human_wins, draws: \$draws\n";        return \$report;    }} sub main {    GetOptions( 'quiet' => \my \$quiet );    greet() if !\$quiet;    while (1) {        print_next_line() if !\$quiet;        my \$input = get_input();        last unless \$input;        if ( \$input eq 'error' ) {            print "I don't understand!\n" if !\$quiet;            redo;        }        my \$comp_choice = Game::get_comp_choice();        Game::save_human_choice(\$input);        my \$result = Game::make_turn( \$input, \$comp_choice );        describe_turn_result( \$input, \$comp_choice, \$result )          if !\$quiet;    }    print Game::get_final_report();} sub greet {    print "Welcome to the Rock-Paper-Scissors game!\n"      . "Choose 'rock', 'paper' or 'scissors'\n"      . "Enter empty line or 'quit' to quit\n";} sub print_next_line {    print 'Your choice: ';} sub get_input {    my \$input = <>;    print "\n" and return if !\$input;    # EOF    chomp \$input;    return if !\$input or \$input =~ m/\A \s* q/xi;    return         ( \$input =~ m/\A \s* r/xi ) ? 'rock'      : ( \$input =~ m/\A \s* p/xi ) ? 'paper'      : ( \$input =~ m/\A \s* s/xi ) ? 'scissors'      :                               'error';} sub describe_turn_result {    my ( \$human_ch, \$comp_ch, \$result ) = @_;    print "You chose \u\$human_ch, I chose \u\$comp_ch. \$result\n";} main(); `

Example input can be generated as follows:

` perl -e '@c=qw(r p s); for(1..10000){ print \$c[ rand() < 0.75 ? 0 : int rand(2) + 1 ], "\n" }' | perl rps.pl --quiet `

Output:

```You chose:
rock     = 7542 times,
paper    = 1204 times,
scissors = 1254 times,
I chose:
rock     = 1275 times,
paper    = 7460 times,
scissors = 1265 times,
Turns: 10000
I won: 5920, you won: 2012, draws: 2068

```

Example of an interactive session:

```Welcome to the Rock-Paper-Scissors game!
Choose 'rock', 'paper' or 'scissors'
Enter empty line or 'quit' to quit
You chose Scissors, I chose Paper. You win!
You chose Scissors, I chose Rock. I win!
You chose Scissors, I chose Rock. I win!
You chose Scissors, I chose Rock. I win!
You chose Scissors, I chose Rock. I win!
You chose Paper, I chose Rock. You win!
You chose Scissors, I chose Rock. I win!
You chose:
rock     = 0 times,
paper    = 1 times,
scissors = 6 times,
I chose:
rock     = 6 times,
paper    = 1 times,
scissors = 0 times,
Turns: 7
I won: 5, you won: 2, draws: 0
```

## Perl 6

This is slightly more complicated than it could be; it is a general case framework with input filtering. It weights the computers choices based on your previous choices. Type in at least the first two characters of your choice, or just hit enter to quit. Customize it by supplying your own %vs options/outcomes.

Here is standard Rock-Paper-Scissors.

`my %vs = (    options => [<Rock Paper Scissors>],    ro => {        ro => [ 2, ''                        ],        pa => [ 1, 'Paper covers Rock: '     ],        sc => [ 0, 'Rock smashes Scissors: ' ]    },    pa => {        ro => [ 0, 'Paper covers Rock: '    ],        pa => [ 2, ''                       ],        sc => [ 1, 'Scissors cut Paper: '   ]    },    sc => {        ro => [ 1, 'Rock smashes Scissors: '],        pa => [ 0, 'Scissors cut Paper: '   ],        sc => [ 2, ''                       ]    }); my %choices = %vs<options>.map({; \$_.substr(0,2).lc => \$_ });my \$keys    = %choices.keys.join('|');my \$prompt  = %vs<options>.map({\$_.subst(/(\w\w)/, -> \$/ {"[\$0]"})}).join(' ')~"? ";my %weight  = %choices.keys »=>» 1; my @stats = 0,0,0;my \$round; while my \$player = (prompt "Round {++\$round}: " ~ \$prompt).lc {    \$player.=substr(0,2);    say 'Invalid choice, try again.' and \$round-- and next      unless \$player.chars == 2 and \$player ~~ /<\$keys>/;    my \$computer = (flat %weight.keys.map( { \$_ xx %weight{\$_} } )).pick;    %weight{\$_.key}++ for %vs{\$player}.grep( { \$_.value[0] == 1 } );    my \$result = %vs{\$player}{\$computer}[0];    @stats[\$result]++;    say "You chose %choices{\$player},  Computer chose %choices{\$computer}.";    print %vs{\$player}{\$computer}[1];    print ( 'You win!', 'You Lose!','Tie.' )[\$result];    say " - (W:{@stats[0]} L:{@stats[1]} T:{@stats[2]})\n",};`
Example output:
```Round 1: [Ro]ck [Pa]per [Sc]issors? ro
You chose Rock,  Computer chose Paper.
Paper covers Rock: You Lose! - (W:0 L:1 T:0)

Round 2: [Ro]ck [Pa]per [Sc]issors? pa
You chose Paper,  Computer chose Scissors.
Scissors cut Paper: You Lose! - (W:0 L:2 T:0)

Round 3: [Ro]ck [Pa]per [Sc]issors? pa
You chose Paper,  Computer chose Scissors.
Scissors cut Paper: You Lose! - (W:0 L:3 T:0)

Round 4: [Ro]ck [Pa]per [Sc]issors? ro
You chose Rock,  Computer chose Rock.
Tie. - (W:0 L:3 T:1)

Round 5: [Ro]ck [Pa]per [Sc]issors? sc
You chose Scissors,  Computer chose Scissors.
Tie. - (W:0 L:3 T:2)
...```

Here is example output from the same code only with a different %vs data structure implementing Rock-Paper-Scissors-Lizard-Spock.

`my %vs = (    options => [<Rock Paper Scissors Lizard Spock>],    ro => {        ro => [ 2, ''                            ],        pa => [ 1, 'Paper covers Rock: '         ],        sc => [ 0, 'Rock smashes Scissors: '     ],        li => [ 0, 'Rock crushes Lizard: '       ],        sp => [ 1, 'Spock vaporizes Rock: '      ]    },    pa => {        ro => [ 0, 'Paper covers Rock: '         ],        pa => [ 2, ''                            ],        sc => [ 1, 'Scissors cut Paper: '        ],        li => [ 1, 'Lizard eats Paper: '         ],        sp => [ 0, 'Paper disproves Spock: '     ]    },    sc => {        ro => [ 1, 'Rock smashes Scissors: '     ],        pa => [ 0, 'Scissors cut Paper: '        ],        sc => [ 2, ''                            ],        li => [ 0, 'Scissors decapitate Lizard: '],        sp => [ 1, 'Spock smashes Scissors: '    ]    },    li => {        ro => [ 1, 'Rock crushes Lizard: '       ],        pa => [ 0, 'Lizard eats Paper: '         ],        sc => [ 1, 'Scissors decapitate Lizard: '],        li => [ 2, ''                            ],        sp => [ 0, 'Lizard poisons Spock: '      ]    },    sp => {        ro => [ 0, 'Spock vaporizes Rock: '      ],        pa => [ 1, 'Paper disproves Spock: '     ],        sc => [ 0, 'Spock smashes Scissors: '    ],        li => [ 1, 'Lizard poisons Spock: '      ],        sp => [ 2, ''                            ]    });`
```Round 1: [Ro]ck [Pa]per [Sc]issors [Li]zard [Sp]ock? li
You chose Lizard,  Computer chose Scissors.
Scissors decapitate Lizard: You Lose! - (W:0 L:1 T:0)

Round 2: [Ro]ck [Pa]per [Sc]issors [Li]zard [Sp]ock? sp
You chose Spock,  Computer chose Paper.
Paper disproves Spock: You Lose! - (W:0 L:2 T:0)

Round 3: [Ro]ck [Pa]per [Sc]issors [Li]zard [Sp]ock? ro
You chose Rock,  Computer chose Lizard.
Rock crushes Lizard: You Win! - (W:1 L:2 T:0)

Round 4: [Ro]ck [Pa]per [Sc]issors [Li]zard [Sp]ock? ro
You chose Rock,  Computer chose Scissors.
Rock smashes Scissors: You win! - (W:2 L:2 T:0)

Round 5: [Ro]ck [Pa]per [Sc]issors [Li]zard [Sp]ock? li
You chose Lizard,  Computer chose Paper.
Lizard eats Paper: You win! - (W:3 L:2 T:0)
...```

## Phix

`--standard gameconstant rule3 = {"rock blunts scissors",                  "paper wraps rock",                  "scissors cut paper"}--extended versionconstant rule5 = {"rock blunts scissors",                  "rock crushes lizard",                  "paper wraps rock",                  "paper disproves spock",                  "scissors cut paper",                  "scissors decapitate lizard",                  "lizard eats paper",                  "lizard poisons spock",                  "spock smashes scissors",                  "spock vaporizes rock"} constant rules = iff(rand(2)=1?rule3:rule5) sequence what = {}sequence beats = {}string wkeys = ""string question = "What is your move "integer choices, hsumsequence history, cplays, pplays object x, verb, y     for i=1 to length(rules) do        {x} = split(rules[i])        if not find(x,what) then            what = append(what,x)            if find(x[1],wkeys) then                wkeys = append(wkeys,x[\$])                question &= x[1..-2]&"("&x[\$]&"), "            else                wkeys = append(wkeys,x[1])                question &= "("&x[1]&")"&x[2..\$]&", "            end if        end if    end for    choices = length(wkeys)    history = repeat(1,choices)    hsum = 3    cplays = repeat(0,choices)    pplays = repeat(0,choices)    beats = repeat(repeat(0,choices),choices)    question[-2] = '?'    for i=1 to length(rules) do        {x,verb,y} = split(rules[i])        beats[find(x,what)][find(y,what)] = verb    end for integer cmove, pmove, draws = 0, pwins = 0, cwins = 0    while 1 do        cmove = rand(hsum)        for i=1 to choices do            cmove -= history[i]            if cmove<=0 then                -- predicted user choice of i, find whatever beats it                for j=1 to choices do                    if string(beats[j][i]) then                        cmove = j                        exit                    end if                end for                exit            end if        end for        puts(1,question)        while 1 do            pmove = lower(wait_key())            if pmove='q' then exit end if            pmove = find(pmove,wkeys)            if pmove!=0 then exit end if        end while        if pmove='q' then exit end if         printf(1,"you: %s, me: %s, ",{what[pmove],what[cmove]})        cplays[cmove] += 1        pplays[pmove] += 1        if cmove=pmove then            printf(1,"a draw.\n")            draws += 1        else            if string(beats[cmove][pmove]) then                printf(1,"%s %s %s. I win.\n",{what[cmove],beats[cmove][pmove],what[pmove]})                cwins += 1            elsif string(beats[pmove][cmove]) then                printf(1,"%s %s %s. You win.\n",{what[pmove],beats[pmove][cmove],what[cmove]})                pwins += 1            else                ?9/0    -- sanity check            end if        end if        history[pmove] += 1        hsum += 1    end while    printf(1,"\n\nYour wins:%d, My wins:%d, Draws:%d\n",{pwins,cwins,draws})    printf(1,"\n\nYour wins:%d, My wins:%d, Draws:%d\n",{pwins,cwins,draws})    printf(1,"       ") for i=1 to choices do   printf(1,"%9s",what[i])     end for    printf(1,"\nyou: ") for i=1 to choices do   printf(1,"%9d",pplays[i])   end for    printf(1,"\n me: ") for i=1 to choices do   printf(1,"%9d",cplays[i])   end for`
Output:
```What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: scissors, rock blunts scissors. You win.
What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: rock, a draw.
What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: paper, paper wraps rock. I win.
What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: rock, a draw.
What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: paper, paper wraps rock. I win.
What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: paper, paper wraps rock. I win.
What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: paper, paper wraps rock. I win.
What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: paper, paper wraps rock. I win.
What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: paper, paper wraps rock. I win.
What is your move (r)ock, (p)aper, (s)cissors? you: rock, me: paper, paper wraps rock. I win.
What is your move (r)ock, (p)aper, (s)cissors?

rock    paper scissors
you:        10        0        0
me:         2        7        1
```

## PHP

Use the url bar to play

e.g: www.example.com/rockpaper.php?moves=paper
www.example.com/rockpaper.php?moves=rock

`  <?phpecho "<h1>" . "Choose: ROCK - PAPER - SCISSORS" . "</h1>";echo "<h2>";echo ""; \$player = strtoupper( \$_GET["moves"] );\$wins = [    'ROCK' => 'SCISSORS',    'PAPER' => 'ROCK',    'SCISSORS' => 'PAPER'  ];\$a_i = array_rand(\$wins);echo "<br>";echo "Player chooses " . "<i style=\"color:blue\">" . \$player . "</i>";echo "<br>";echo "<br>" . "A.I chooses " . "<i style=\"color:red\">"  . \$a_i . "</i>"; \$results = "";if (\$player == \$a_i){\$results = "Draw";} else if(\$wins[\$a_i] == \$player ){  \$results = "A.I wins";} else {  \$results = "Player wins";} echo "<br>" . \$results;?> `

## PicoLisp

`(use (C Mine Your)   (let (Rock 0  Paper 0  Scissors 0)      (loop         (setq Mine            (let N (if (gt0 (+ Rock Paper Scissors)) (rand 1 @) 0)               (seek                  '((L) (le0 (dec 'N (caar L))))                  '(Rock Paper Scissors .) ) ) )         (prin "Enter R, P or S to play, or Q to quit: ")         (loop            (and (= "Q" (prinl (setq C (uppc (key))))) (bye))            (T (setq Your (find '((S) (pre? C S)) '(Rock Paper Scissors))))            (prinl "Bad input - try again") )         (prinl            "I say " (cadr Mine) ", You say " Your ": "            (cond               ((== Your (cadr Mine)) "Draw")               ((== Your (car Mine)) "I win")               (T "You win") ) )         (inc Your) ) ) )`

## PL/I

` rock: procedure options (main);   /* 30 October 2013 */   declare move character (1), cm fixed binary;    put ('The Rock-Paper-Scissors game');   put skip list ("please type 'r' for rock, 'p' for paper, 's' for scissors.");   put skip list ("Anything else finishes:");   do forever;      get edit (move) (a(1));      move = lowercase(move);      if index('rpsq', move) = 0 then iterate;      if move = 'q' then stop;      cm = random()*3; /* computer moves: 0 = rock, 1 = paper, 2 = scissors */      select (cm);         when (0) select (move);                     when ('r') put list ('rock and rock: A draw');                     when ('p') put list ('paper beats rock: You win');                     when ('s') put list ('rock breaks scissors: I win');                  end;         when (1) select (move);                     when ('r') put list ('paper beats rock: I win');                     when ('p') put list ('paper and paper: A draw');                     when ('s') put list ('scissors cut paper: You win');                  end;         when (2) select (move);                     when ('r') put list ('rock breaks scissors: You win');                     when ('p') put list ('scissors cuts paper: I win');                     when ('s') put list ('Scissors and Scissors: A draw');                  end;      end;   end;end rock; `

## PureBasic

`Enumeration  ;choices are in listed according to their cycle, weaker followed by stronger  #rock  #paper  #scissors  #numChoices ;this comes after all possible choicesEndEnumeration ;give names to each of the choicesDim choices.s(#numChoices - 1)choices(#rock) = "rock"choices(#paper) = "paper"choices(#scissors) = "scissors" Define gameCountDim playerChoiceHistory(#numChoices - 1) Procedure weightedRandomChoice()  Shared gameCount, playerChoiceHistory()  Protected x = Random(gameCount - 1), t, c   For i = 0 To #numChoices - 1    t + playerChoiceHistory(i)    If t >= x      c = i      Break    EndIf  Next   ProcedureReturn (c + 1) % #numChoicesEndProcedure If OpenConsole()  PrintN("Welcome to the game of rock-paper-scissors")  PrintN("Each player guesses one of these three, and reveals it at the same time.")  PrintN("Rock blunts scissors, which cut paper, which wraps stone.")  PrintN("If both players choose the same, it is a draw!")  PrintN("When you've had enough, choose Q.")   Define computerChoice, playerChoice, response.s  Define playerWins, computerWins, draw, quit   computerChoice = Random(#numChoices - 1)  Repeat    Print(#CRLF\$ + "What is your move (press R, P, or S)?")    Repeat      response = LCase(Input())    Until FindString("rpsq", response) > 0     If response = "q":      quit = 1    Else      gameCount + 1      playerChoice = FindString("rps", response) - 1       result = (playerChoice - computerChoice + #numChoices) % #numChoices      Print("You chose " + choices(playerChoice) + " and I chose " + choices(computerChoice))      Select result        Case 0          PrintN(". It's a draw.")          draw + 1        Case 1          PrintN(". You win!")          playerWins + 1        Case 2          PrintN(". I win!")          computerWins + 1      EndSelect      playerChoiceHistory(playerChoice) + 1      computerChoice = weightedRandomChoice()    EndIf   Until quit   Print(#CRLF\$ + "You chose: ")  For i = 0 To #numChoices - 1    Print(choices(i) + " " + StrF(playerChoiceHistory(i) * 100 / gameCount, 1) + "%; ")  Next  PrintN("")  PrintN("You won " + Str(playerWins) + ", and I won " + Str(computerWins) + ". There were " + Str(draw) + " draws.")  PrintN("Thanks for playing!")   Print(#CRLF\$ + #CRLF\$ + "Press ENTER to exit"): Input()  CloseConsole()EndIf`

Sample output:

```Welcome to the game of rock-paper-scissors
Each player guesses one of these three, and reveals it at the same time.
Rock blunts scissors, which cut paper, which wraps stone.
If both players choose the same, it is a draw!
When you've had enough, choose Q.

What is your move (press R, P, or S)?r
You chose rock and I chose paper. I win!

What is your move (press R, P, or S)?r
You chose rock and I chose paper. I win!

What is your move (press R, P, or S)?r
You chose rock and I chose paper. I win!

What is your move (press R, P, or S)?r
You chose rock and I chose paper. I win!

What is your move (press R, P, or S)?r
You chose rock and I chose paper. I win!

What is your move (press R, P, or S)?s
You chose scissors and I chose paper. You win!

What is your move (press R, P, or S)?r
You chose rock and I chose paper. I win!

What is your move (press R, P, or S)?s
You chose scissors and I chose paper. You win!

What is your move (press R, P, or S)?s
You chose scissors and I chose paper. You win!

What is your move (press R, P, or S)?s
You chose scissors and I chose paper. You win!

What is your move (press R, P, or S)?s
You chose scissors and I chose rock. I win!

What is your move (press R, P, or S)?q

You chose: rock 54.5%; paper 0.0%; scissors 45.5%;
You won 4, and I won 7. There were 0 draws.
Thanks for playing!```

## Python

A light version with limited support for additional rules. New weapons can be introduced, but each can only be beaten by one other weapon.

The `rules` dictionary is of the form `'this': beaten by 'that', etc` as opposed to `'this': beats 'that'`.

`from random import choice rules = {'rock': 'paper', 'scissors': 'rock', 'paper': 'scissors'}previous = ['rock', 'paper', 'scissors'] while True:    human = input('\nchoose your weapon: ')    computer = rules[choice(previous)]  # choose the weapon which beats a randomly chosen weapon from "previous"     if human in ('quit', 'exit'): break     elif human in rules:        previous.append(human)        print('the computer played', computer, end='; ')         if rules[computer] == human:  # if what beats the computer's choice is the human's choice...            print('yay you win!')        elif rules[human] == computer:  # if what beats the human's choice is the computer's choice...            print('the computer beat you... :(')        else: print("it's a tie!")     else: print("that's not a valid choice")`

Output, where player always chooses Rock:

```choose your weapon: rock
the computer played rock; it's a tie!

the computer played scissors; yay you win!

the computer played paper; the computer beat you... :(

the computer played paper; the computer beat you... :(

the computer played paper; the computer beat you... :(```

This is another code. Output is as same as the above output.

`from random import randint hands = ['rock', 'scissors', 'paper']; judge = ['its a tie!', 'the computer beat you... :(', 'yay you win!']while True:    try:        YOU = hands.index(input('Choose your weapon: ')) # YOU = hands.index(raw_input('Choose your weapon: '))   If you use Python2.7    except ValueError:        break    NPC = randint(0, 2)    print('The computer played ' + hands[NPC] + '; ' + judge[YOU-NPC])`

## Rascal

`import Prelude; rel[str, str] whatbeats = {<"Rock", "Scissors">, <"Scissors", "Paper">, <"Paper", "Rock">}; list[str] ComputerChoices = ["Rock", "Paper", "Scissors"]; str CheckWinner(a, b){	if(b == getOneFrom(whatbeats[a]))		return a;	elseif(a == getOneFrom(whatbeats[b]))		return b;	else return "Nobody"; } public str RPS(human){	computer = getOneFrom(ComputerChoices);	x = if(human == "Rock") "Paper"; elseif(human == "Paper") "Scissors"; else "Rock";	ComputerChoices += x;	return "Computer played <computer>. <CheckWinner(human, computer)> wins!";}`

Sample output:

`rascal>RPS("Rock")str: "Computer played Rock. Nobody wins!" rascal>RPS("Rock")str: "Computer played Rock. Nobody wins!" rascal>RPS("Rock")str: "Computer played Scissors. Rock wins!" rascal>RPS("Rock")str: "Computer played Paper. Paper wins!" rascal>RPS("Rock")str: "Computer played Paper. Paper wins!" rascal>RPS("Rock")str: "Computer played Paper. Paper wins!" rascal>RPS("Rock")str: "Computer played Paper. Paper wins!" rascal>RPS("Rock")str: "Computer played Rock. Nobody wins!" rascal>RPS("Rock")str: "Computer played Paper. Paper wins!" rascal>RPS("Rock")str: "Computer played Paper. Paper wins!"`

## Racket

` #lang racket(require math) (define history (make-hash '((paper . 1) (scissors . 1) (rock . 1))))(define total 3) (define (update-history! human-choice)  (set! total (+ total 1))  (hash-update! history human-choice add1 0)) (define (pick-one)  (sample   (discrete-dist '(paper scissors rock)                  (map (λ (x) (hash-ref history x))                       '(scissors paper rock))))) (define (find-winner computer human)  (define order '(scissors paper rock scissors))  (cond     [(eq? computer human)                         'none]    [(eq? (second (member computer order)) human) 'computer]    [                                             'human])) (define (game-loop)  (define computer-choice (pick-one))  (define human-choice (read))  (define winner (find-winner computer-choice human-choice))  (update-history! human-choice)  (displayln (~a "Computer picked " computer-choice ", "                 "human picked " human-choice ", "                 winner " wins."))  (game-loop)) (game-loop) `

## REXX

This REXX program version:

•   allows the human player to abbreviate their choice
•   issues appropriate error messages for an incorrect (or no) choice(s)
•   allows the human player to   QUIT   at any time
•   keeps track of the human player's responses   (to hopefully make future computer winning choices)
•   uses better "English"/grammer,     i.e.:       rock breaks scissors,       and       paper covers rock.
`/*REXX program plays rock─paper─scissors with a human;  tracks what human tends to use. */!= '────────';   err=! '***error***';    @.=0    /*some constants for this program.     */prompt= !  'Please enter one of:     Rock   Paper   Scissors      (or Quit)'\$.p='paper' ;    \$.s='scissors';   \$.r='rock'    /*list of the choices in this program. */t.p=\$.r     ;    t.s=\$.p       ;   t.r=\$.s       /*thingys that beats  stuff.           */w.p=\$.s     ;    w.s=\$.r       ;   w.r=\$.p       /*stuff     "    "   thingys.          */b.p='covers';    b.s='cuts'    ;   b.r='breaks'  /*verbs:   how the choice wins.        */   do forever;   say;   say prompt;   say         /*prompt the CBLF; then get a response.*/  c=word(\$.p \$.s \$.r,   random(1, 3) )           /*choose the computer's first pick.    */  m=max(@.r, @.p, @.s);    c=w.r                 /*prepare to examine the choice history*/  if @.p==m  then c=w.p                          /*emulate JC's:  The Amazing Karnac.   */  if @.s==m  then c=w.s                          /*   "     "      "     "       "      */  c1=left(c, 1)                                  /*C1  is used for faster comparing.    */  parse pull u;            a=strip(u)            /*get the CBLF's choice/pick (answer). */  upper a c1  ;           a1=left(a, 1)          /*uppercase choices, get 1st character.*/  ok=0                                           /*indicate answer isn't OK  (so far).  */       select                                    /*process/verify the  CBLF's  choice.  */       when words(u)==0           then           say  err   'nothing entered'       when words(u)>1            then say  err   'too many choices: '  u       when abbrev('QUIT',    a)  then do;  say ! 'quitting.';      exit;    end       when abbrev('ROCK',    a) |,            abbrev('PAPER',   a) |,            abbrev('SCISSORS',a)  then ok=1      /*Yes?  This is a valid answer by CBLF.*/       otherwise                  say err  'you entered a bad choice: '    u       end   /*select*/   if \ok          then iterate                   /*answer ¬OK?  Then get another choice.*/  @.[email protected].a1+1                                    /*keep a history of the CBLF's choices.*/  say !  'computer chose: '    c  if   a1==  c1  then do;  say !  'draw.';   iterate;  end  if \$.a1==t.c1  then say  !  'the computer wins. '    !  \$.c1  b.c1  \$.a1                 else say  !  'you win! '              !  \$.a1  b.a1  \$.c1  end   /*forever*/                              /*stick a fork in it,  we're all done. */`
output   with various responses from the user   (output shown is a screen scraping):
```──────── Please enter one of:     Rock  Paper  Scissors      (or Quit)

s        ◄■■■■■■■■■■■■■■■ human input.
──────── computer chose:  rock
──────── the computer wins.  ──────── rock breaks scissors

──────── Please enter one of:     Rock  Paper  Scissors      (or Quit)

s        ◄■■■■■■■■■■■■■■■ human input.
──────── computer chose:  rock
──────── the computer wins.  ──────── rock breaks scissors

──────── Please enter one of:     Rock  Paper  Scissors      (or Quit)

s        ◄■■■■■■■■■■■■■■■ human input.
──────── computer chose:  rock
──────── the computer wins.  ──────── rock breaks scissors

──────── Please enter one of:     Rock  Paper  Scissors      (or Quit)

s        ◄■■■■■■■■■■■■■■■ human input.
──────── computer chose:  rock
──────── the computer wins.  ──────── rock breaks scissors

──────── Please enter one of:     Rock  Paper  Scissors      (or Quit)

s        ◄■■■■■■■■■■■■■■■ human input.
──────── computer chose:  rock
──────── the computer wins.  ──────── rock breaks scissors

──────── Please enter one of:     Rock  Paper  Scissors      (or Quit)

p        ◄■■■■■■■■■■■■■■■ human input.
──────── computer chose:  rock
──────── you win!  ──────── paper covers  rock

──────── Please enter one of:     Rock  Paper  Scissors      (or Quit)

q        ◄■■■■■■■■■■■■■■■ human input.
──────── quitting.
```

### extended, 5 choices

This REXX version supports more choices:   rock   paper   scissors   lizard   Spock

`/*REXX pgm plays rock─paper─scissors─lizard─Spock with human; tracks human usage trend. */!= '────────';   err=! '***error***';    @.=0    /*some constants for this REXX program.*/prompt=! 'Please enter one of:   Rock  Paper  SCissors  Lizard  SPock  (Vulcan)     (or Quit)'\$.p='paper'           ; \$.s='scissors'        ; \$.r='rock'          ; \$.L='lizard'      ; \$.v='Spock'              /*names of the thingys*/t.p= \$.r \$.v          ; t.s= \$.p \$.L          ; t.r= \$.s \$.L        ; t.L= \$.p \$.v      ; t.v= \$.r \$.s             /*thingys beats stuff.*/w.p= \$.L \$.s          ; w.s= \$.v \$.r          ; w.r= \$.v \$.p        ; w.L= \$.r \$.s      ; w.v= \$.L \$.p             /*stuff beats thingys.*/b.p='covers disproves'; b.s="cuts decapitates"; b.r='breaks crushes'; b.L="eats poisons"; b.v='vaporizes smashes'  /*how the choice wins.*/whom.1=! 'the computer wins. ' !;     whom.2=! "you win! " !;     win=words(t.p)   do forever;   say;   say prompt;    say        /*prompt CBLF; then get a response.    */  c=word(\$.p \$.s \$.r \$.L \$.v, random(1, 5) )     /*the computer's first choice/pick.    */  m=max(@.r,@.p,@.s,@.L,@.v)                     /*used in examining CBLF's history.    */  if @.p==m  then c=word(w.p, random(1, 2) )     /*emulate JC's  The Amazing Karnac.    */  if @.s==m  then c=word(w.s, random(1, 2) )     /*   "     "     "     "       "       */  if @.r==m  then c=word(w.r, random(1, 2) )     /*   "     "     "     "       "       */  if @.L==m  then c=word(w.L, random(1, 2) )     /*   "     "     "     "       "       */  if @.v==m  then c=word(w.v, random(1, 2) )     /*   "     "     "     "       "       */  c1=left(c, 1)                                  /*C1  is used for faster comparing.    */  parse pull u;            a=strip(u)            /*obtain the CBLF's choice/pick.       */  upper a c1  ;           a1=left(a, 1)          /*uppercase the choices, get 1st char. */  ok=0                                           /*indicate answer isn't  OK  (so far). */       select                                    /* [↓]  process the CBLF's choice/pick.*/       when words(u)==0               then say err    'nothing entered.'       when words(u)>1                then say err    'too many choices: '    u       when abbrev('QUIT',    a)      then do; say !  'quitting.';   exit;   end       when abbrev('LIZARD',  a)   |,            abbrev('ROCK',    a)   |,            abbrev('PAPER',   a)   |,            abbrev('VULCAN',  a)   |,            abbrev('SPOCK',   a,2) |,            abbrev('SCISSORS',a,2)    then ok=1  /*it's a valid choice for the human.   */       otherwise                  say err   'you entered a bad choice: '   u       end   /*select*/   if \ok          then iterate                   /*answer ¬OK?  Then get another choice.*/  @.a1= @.a1 + 1                                 /*keep a history of the CBLF's choices.*/  say ! 'computer chose: '  c  if a1==c1  then say !  'draw.'                 /*Oh rats!  The contest ended up a draw*/             else do who=1  for 2                /*either the computer or the CBLF won. */                  if who==2  then parse value  a1 c1   with   c1 a1                       do j=1  for win                                  /*see who won.  */                       if \$.a1 \== word(t.c1, j)  then iterate          /*not this 'un. */                       say whom.who  \$.c1  word(b.c1, j)  \$.a1          /*notify winner.*/                       leave                                            /*leave  J loop.*/                       end   /*j*/                  end        /*who*/  end   /*forever*/                              /*stick a fork in it,  we're all done. */`
output   is similar to the 1st REXX version.

## Ring

` # Project : Rock-paper-scissors see "welcome to the game of rock-paper-scissors. each player guesses one of these three, and reveals it at the same time.rock blunts scissors, which cut paper, which wraps stone.if both players choose the same, it is a draw!when you've had enough, choose q."g = ["rock","paper","scissors"]total=0 draw=0pwin=0 cwin=0see "what is your move (press r, p, or s)?"while true        c=random(2)+1        give q          gs = floor((substr("rpsq",lower(q))))        if gs>3 or gs<1           summarise()           exit        ok        total = total + 1        see"you chose " + g[gs] + " and i chose " + g[c] + nl        temp = gs-c        if temp = 0           see ". it's a draw"           draw = draw + 1        ok        if temp = 1 or temp = -2           see ". you win!"           pwin = pwin + 1        ok        if temp = (-1) or temp = 2            see ". i win!"            cwin = cwin + 1        okend `

Output:

```welcome to the game of rock-paper-scissors.
each player guesses one of these three, and reveals it at the same time.
rock blunts scissors, which cut paper, which wraps stone.
if both players choose the same, it is a draw!
when you've had enough, choose q.

what is your move (press r, p, or s)?
r
you chose rock and i chose rock
. it's a draw
p
you chose paper and i chose paper
. it's a draw
s
you chose scissors and i chose rock
. i win!
R
you chose rock and i chose paper
. i win!
P
you chose paper and i chose paper
. it's a draw
S
you chose scissors and i chose paper
. you win!
q
you won 1, and i won 2. there were 3 draws
thanks for playing!
```

## Ruby

`class RockPaperScissorsGame  CHOICES = %w[rock paper scissors quit]  BEATS = {    'rock'     => 'paper',    'paper'    => 'scissors',    'scissors' => 'rock',  }   def initialize()    @plays = {      'rock'     => 1,      'paper'    => 1,      'scissors' => 1,    }    @score = [0, 0, 0]          # [0]:Human wins, [1]:Computer wins, [2]:draw     play  end   def humanPlay    loop do      print "\nYour choice: #{CHOICES}? "      answer = STDIN.gets.strip.downcase      next if answer.empty?      idx = CHOICES.find_index {|choice| choice.match(/^#{answer}/)}      return CHOICES[idx] if idx      puts "invalid answer, try again"    end  end   def computerPlay    total = @plays.values.reduce(:+)    r = rand(total) + 1    sum = 0    CHOICES.each do |choice|      sum += @plays[choice]      return BEATS[choice] if r <= sum    end  end   def play    loop do      h = humanPlay      break if h == "quit"      c = computerPlay      print "H: #{h}, C: #{c} => "       # only update the human player's history after the computer has chosen      @plays[h] += 1       if h == c        puts "draw"        @score[2] += 1      elsif h == BEATS[c]        puts "Human wins"        @score[0] += 1      else        puts "Computer wins"        @score[1] += 1      end      puts "score: human=%d, computer=%d, draw=%d" % [*@score]    end    @plays.each_key{|k| @plays[k] -= 1}    puts "\nhumans chose #{@plays}"  endend RockPaperScissorsGame.new`

sample game where human always chooses rock:

```Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: rock => draw
score: human=0, computer=0, draw=1

Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: scissors => Human wins
score: human=1, computer=0, draw=1

Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: paper => Computer wins
score: human=1, computer=1, draw=1

Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: paper => Computer wins
score: human=1, computer=2, draw=1

Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: paper => Computer wins
score: human=1, computer=3, draw=1

Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: paper => Computer wins
score: human=1, computer=4, draw=1

Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: paper => Computer wins
score: human=1, computer=5, draw=1

Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: paper => Computer wins
score: human=1, computer=6, draw=1

Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: rock => draw
score: human=1, computer=6, draw=2

Your choice: ["rock", "paper", "scissors", "quit"]? r
H: rock, C: paper => Computer wins
score: human=1, computer=7, draw=2

Your choice: ["rock", "paper", "scissors", "quit"]? q

humans chose {"rock"=>10, "paper"=>0, "scissors"=>0}
```

## Run BASIC

`pri\$ = "RSPR" rps\$ = "Rock,Paper,Sissors"[loop]button #r, "Rock",    [r]button #p, "Paper",   [p]button #s, "Scissors",[s]button #q, "Quit",    [q]wait[r] y = 1 :goto [me][p] y = 2 :goto [me][s] y = 3[me]clsy\$ = word\$(rps\$,y,",")m  = int((rnd(0) * 2) + 1)m\$ = word\$(rps\$,m,",")print chr\$(10);"You Chose:";y\$;" I chose:";m\$yp = instr(pri\$,left\$(y\$,1))mp = instr(pri\$,left\$(m\$,1))if yp = 1 and mp = 3 then mp = 0if mp = 1 and yp = 3 then yp = 0if yp < mp then print "You win"if yp = mp then print "Tie"if yp > mp then print "I win"goto [loop]wait [q] clsprint "Good Bye! I enjoyed the game"end `

## Rust

`extern crate rand;#[macro_use]extern crate rand_derive; use std::io;use rand::Rng;use Choice::*; #[derive(PartialEq, Clone, Copy, Rand, Debug)]enum Choice {    Rock,    Paper,    Scissors,} fn beats(c1: Choice, c2: Choice) -> bool {    (c1 == Rock && c2 == Scissors) || (c1 == Scissors && c2 == Paper) || (c1 == Paper && c2 == Rock)} fn ai_move<R: Rng>(rng: &mut R, v: [usize; 3]) -> Choice {    // weighted random choice, a dynamic version of `rand::distributions::WeightedChoice`    let rand = rng.gen_range(0, v[0] + v[1] + v[2]);    if rand < v[0] {        Paper    } else if rand < v[0] + v[1] {        Scissors    } else {        Rock    }} fn main() {    let mut rng = rand::thread_rng();     println!("Rock, paper, scissors!");    let mut ai_choice: Choice = rng.gen();    let mut ucf = [0, 0, 0]; // user choice frequency    let mut score = [0, 0];     loop {        println!("Please input your move: 'r', 'p' or 's'. Type 'q' to quit");         let mut input = String::new();        io::stdin()            .read_line(&mut input)            .expect("failed to read line");        let u_choice = match input.to_lowercase().trim() {            s if s.starts_with('r') => {                ucf[0] += 1;                Rock            }            s if s.starts_with('p') => {                ucf[1] += 1;                Paper            }            s if s.starts_with('s') => {                ucf[2] += 1;                Scissors            }            s if s.starts_with('q') => break,            _ => {                println!("Please enter a correct choice!");                continue;            }        };        println!("You chose {:?}, I chose {:?}.", u_choice, ai_choice);        if beats(u_choice, ai_choice) {            score[0] += 1;            println!("You win!");        } else if u_choice == ai_choice {            println!("It's a tie!");        } else {            score[1] += 1;            println!("I win!");        }        println!("-Score: You {}, Me {}", score[0], score[1]);         // only after the 1st iteration the AI knows the stats and can make        // its weighted random move        ai_choice = ai_move(&mut rng, ucf);    }    println!("Thank you for the game!");}`

## Scala

You can invoke this game with an arbitrary number of weapons:

`object RockPaperScissors extends App {  import scala.collection.mutable.LinkedHashMap  def play(beats: LinkedHashMap[Symbol,Set[Symbol]], played: scala.collection.Map[Symbol,Int]) {    val h = readLine(s"""Your move (\${beats.keys mkString ", "}): """) match {      case null => println; return      case "" => return      case s => Symbol(s)    }    beats get h match {      case Some(losers) =>        def weighted(todo: Iterator[(Symbol,Int)], rand: Int, accum: Int = 0): Symbol = todo.next match {          case (s, i) if rand <= (accum + i) => s          case (_, i) => weighted(todo, rand, accum + i)        }        val c = weighted(played.toIterator, 1 + scala.util.Random.nextInt(played.values.sum)) match {          // choose an opponent that would beat the player's anticipated move          case h => beats.find{case (s, l) => l contains h}.getOrElse(beats.head)._1        }        print(s"  My move: \$c\n  ")        c match {          case c if losers contains c => println("You won")          case c if beats(c) contains h => println("You lost")          case _ => println("We drew") // or underspecified        }      case x => println("  Unknown weapon, try again.")    }    play(beats, played get h match {      case None => played      case Some(count) => played.updated(h, count + 1)    })  }   def play(beats: LinkedHashMap[Symbol,Set[Symbol]]): Unit =      play(beats, beats.mapValues(_ => 1)) // init with uniform probabilities   play(LinkedHashMap(    'rock -> Set('lizard, 'scissors),    'paper -> Set('rock, 'spock),    'scissors -> Set('paper, 'lizard),    'lizard -> Set('spock, 'paper),    'spock -> Set('scissors, 'rock)  ))}`
Output:
```Your move ('rock, 'paper, 'scissors, 'lizard, 'spock): paper
My move: 'paper
We drew
Your move ('rock, 'paper, 'scissors, 'lizard, 'spock): scissors
My move: 'paper
You won
Your move ('rock, 'paper, 'scissors, 'lizard, 'spock): rock
My move: 'scissors
You won
Your move ('rock, 'paper, 'scissors, 'lizard, 'spock): rock
My move: 'rock
We drew
Your move ('rock, 'paper, 'scissors, 'lizard, 'spock): rock
My move: 'paper
You lost
Your move ('rock, 'paper, 'scissors, 'lizard, 'spock): rock
My move: 'rock
We drew
Your move ('rock, 'paper, 'scissors, 'lizard, 'spock): rock
My move: 'paper
You lost
Your move ('rock, 'paper, 'scissors, 'lizard, 'spock): rock
My move: 'paper
You lost```

Here's another code: (I refactored the above code, it is more functional, more testable )

`object RockPaperScissors extends App {    def beats = Map(        'rock -> Set('lizard, 'scissors),        'paper -> Set('rock, 'spock),        'scissors -> Set('paper, 'lizard),        'lizard -> Set('spock, 'paper),        'spock -> Set('scissors, 'rock)    )    // init with uniform probabilities    def initPlayed = beats.mapValues(_ => 1)    def input = Symbol(readLine(s"""Your move (\${beats.keys mkString ", "}): """))    def random(max: Int) = scala.util.Random.nextInt(max)    def display(text: String) = print(text)     def weighted(todo: Iterator[(Symbol,Int)], rand: Int, accum: Int = 0): Symbol = todo.next match {        case (s, i) if rand <= (accum + i) => s        case (_, i) => weighted(todo, rand, accum + i)    }     def calcMyMove(random: Int => Int, played: Map[Symbol,Int]) = {        weighted(played.toIterator, 1 + random(played.values.sum)) match {        // choose an opponent that would beat the player's anticipated move            case h => beats.find{case (s, l) => l contains h}.getOrElse(beats.head)._1        }    }     case class Result(text: String, won: Int, lost: Int, drew: Int) {        override def toString = s"\$text. Won: \$won, Lost: \$lost, Drew: \$drew"    }     def getResult(userWeapon: Symbol, myMove: Symbol, result: Result) = {        if (beats(userWeapon) contains myMove)            result.copy(text = "You won", won = result.won + 1)        else if (beats(myMove) contains userWeapon)            result.copy(text = "You lost", lost = result.lost + 1)        else result.copy(text = "We drew", drew = result.drew + 1)     }     def play(input: => Symbol, display: String => Unit, random: Int => Int)        (played: Map[Symbol,Int], result: Result): Result = {        val userWeapon = input        if (userWeapon != Symbol("")) {            val newResult = if (beats contains userWeapon) {                val myMove = calcMyMove(random, played)                display(s"  My move: \$myMove\n  ")                getResult(userWeapon, myMove, result)            } else {                result.copy(text = "  Unknown weapon, try again")            }            display(newResult + "\n")            play(input, display, random)(played get userWeapon match {                case None => played                case Some(count) => played.updated(userWeapon, count + 1)            }, newResult)        } else result    }     override def main(args: Array[String]): Unit =        play(input, display, random)(initPlayed, Result("Start", 0, 0, 0))}`
Output:
```Your move ('spock, 'rock, 'lizard, 'paper, 'scissors): rock
My move: 'rock
We drew. Won: 0, Lost: 0, Drew: 1
Your move ('spock, 'rock, 'lizard, 'paper, 'scissors): spock
My move: 'spock
We drew. Won: 0, Lost: 0, Drew: 2
Your move ('spock, 'rock, 'lizard, 'paper, 'scissors): lizard
My move: 'spock
You won. Won: 1, Lost: 0, Drew: 2
Your move ('spock, 'rock, 'lizard, 'paper, 'scissors): scissors
My move: 'spock
You lost. Won: 1, Lost: 1, Drew: 2
Your move ('spock, 'rock, 'lizard, 'paper, 'scissors): scissors
My move: 'spock
You lost. Won: 1, Lost: 2, Drew: 2
Your move ('spock, 'rock, 'lizard, 'paper, 'scissors): spock
My move: 'rock
You won. Won: 2, Lost: 2, Drew: 2```

## Seed7

The program reads the possible commands (1, 2, 3, q) as single keypresses from the KEYBOARD with getc. It is also possible to quit the program with q.

 This example is incorrect. Please fix the code and remove this message.Details: This example does not seem to use the weighted average AI from the task description.
`\$ include "seed7_05.s7i";\$ include "keybd.s7i"; const array string: rockPaperScissors is [] ("Rock", "Paper", "Scissors"); const proc: main is func  local    var char: command is ' ';    var integer: user is 0;    var integer: comp is 0;  begin    writeln("Hello, Welcome to rock-paper-scissors");    repeat      write("Please type in 1 for Rock, 2 for Paper, 3 for Scissors, q to quit ");      flush(OUT);      repeat        command := lower(getc(KEYBOARD));      until command in {'1', '2', '3', 'q'};      writeln(command);      if command <> 'q' then        user := integer parse str(command);        comp := rand(1, 3);        writeln("You Played: " <& rockPaperScissors[user]);        writeln("Computer Played: " <& rockPaperScissors[comp]);        if comp = user then          writeln("You Tied");        elsif succ(comp) = user or user + 2 = comp then          writeln("Yay, You Won!");        else          writeln("Sorry, You Lost!");        end if;      end if;    until command = 'q';    writeln("Goodbye! Thanks for playing!");  end func;`

Sample run:

```Hello, Welcome to rock-paper-scissors
Please type in 1 for Rock, 2 for Paper, 3 for Scissors, q to quit 1
You Played: Rock
Computer Played: Scissors
Yay, You Won!
Please type in 1 for Rock, 2 for Paper, 3 for Scissors, q to quit 2
You Played: Paper
Computer Played: Scissors
Sorry, You Lost!
Please type in 1 for Rock, 2 for Paper, 3 for Scissors, q to quit 3
You Played: Scissors
Computer Played: Paper
Yay, You Won!
Please type in 1 for Rock, 2 for Paper, 3 for Scissors, q to quit q
Goodbye! Thanks for playing!
```

## Sidef

`const rps = %w(r p s) const msg = [    "Rock breaks scissors",    "Paper covers rock",    "Scissors cut paper",] say <<"EOT"\n>> Rock Paper Scissors <<\n** Enter 'r', 'p', or 's' as your play.** Enter 'q' to exit the game.** Running score shown as <your wins>:<my wins>EOT var plays   = 0var aScore  = 0var pScore  = 0var pcf     = [0,0,0]      # pcf = player choice frequencyvar aChoice = pick(0..2)   # ai choice for first play is completely random loop {    var pi = Sys.scanln("Play: ")    pi == 'q' && break     var pChoice = rps.index(pi)     if (pChoice == -1) {        STDERR.print("Invalid input!\n")        next    }     ++pcf[pChoice]    ++plays     # show result of play    ">> My play: %-8s".printf(rps[aChoice])     given ((aChoice - pChoice + 3) % 3) {        when (0) { say "Tie." }        when (1) { "%-*s %s".printlnf(30, msg[aChoice], 'My point');   aScore++ }        when (2) { "%-*s %s".printlnf(30, msg[pChoice], 'Your point'); pScore++ }    }     # show score    "%-6s".printf("%d:%d" % (pScore, aScore))     # compute ai choice for next play    given (plays.rand.int) { |rn|        case (rn < pcf[0])        { aChoice = 1 }        case (pcf[0]+pcf[1] > rn) { aChoice = 2 }        default                   { aChoice = 0 }    }}`

Sample run:

```>> Rock Paper Scissors <<

** Enter 'r', 'p', or 's' as your play.
** Enter 'q' to exit the game.
** Running score shown as <your wins>:<my wins>

Play: r
>> My play: s       Rock breaks scissors           Your point
1:0   Play: p
>> My play: p       Tie.
1:0   Play: r
>> My play: s       Rock breaks scissors           Your point
2:0   Play: s
>> My play: p       Scissors cut paper             Your point
3:0   Play: r
>> My play: p       Paper covers rock              My point
3:1   Play: p
>> My play: r       Paper covers rock              Your point
4:1   Play: q
```

## SuperCollider

```// play it in the REPL, evaluating line by line

a = RockPaperScissors.new;
a.next(Scissors);
a.next(Scissors);
a.next(Scissors);
a.next(Paper);
```

An implementation using classes

```Rock {

*play { |other|
^other.rock + this + "against" + other
}

*rock {
^"tie"
}

*paper {
^"loses"
}

*scissors {
^"wins"
}

*losesAgainst {
^Paper
}

}

Paper {

*play { |other|
^other.paper + this + "against" + other
}

*paper {
^"tie"
}

*scissors {
^"loses"
}

*rock {
^"wins"
}

*losesAgainst {
^Scissors
}

}

Scissors {

*play { |other|
^other.scissors + this + "against" + other
}

*scissors {
^"tie"
}

*rock {
^"loses"
}

*paper {
^"wins"
}

*losesAgainst {
^Rock
}

}

RockPaperScissors {
var opponentMoves;

*new {
^super.new.init
}

init {
opponentMoves = Bag.new;
}

findBestMatch {
var typicalMove = opponentMoves.wchoose;
if(typicalMove.isNil) { ^[Rock, Paper, Scissors].choose };
^typicalMove.losesAgainst
}

next { |otherMove|
var myMove = this.findBestMatch;
^play(otherMove, myMove)
}

}
```

## Swift

`enum Choice: CaseIterable {  case rock  case paper  case scissors  case lizard  case spock} extension Choice {  var weaknesses: Set<Choice> {    switch self {      case .rock:        return [.paper, .spock]      case .paper:        return [.scissors, .lizard]      case .scissors:        return [.rock, .spock]      case .lizard:        return [.rock, .scissors]      case .spock:        return [.paper, .lizard]    }  }} struct Game {  private(set) var history: [(Choice, Choice)] = []  private(set) var p1Score: Int = 0  private(set) var p2Score: Int = 0   mutating func play(_ p1Choice: Choice, against p2Choice: Choice) {    history.append((p1Choice, p2Choice))    if p2Choice.weaknesses.contains(p1Choice) {      p1Score += 1    } else if p1Choice.weaknesses.contains(p2Choice) {      p2Score += 1    }  }} func aiChoice(for game: Game) -> Choice {  if let weightedWeekness = game.history.flatMap({ \$0.0.weaknesses }).randomElement() {    return weightedWeekness  } else {    // If history is empty, return random Choice    return Choice.allCases.randomElement()!  }} var game = Game()print("Type your choice to play a round, or 'q' to quit")loop: while true {  let choice: Choice  switch readLine().map({ \$0.lowercased() }) {    case "r", "rock":      choice = .rock    case "p", "paper":      choice = .paper    case "scissors":      choice = .scissors    case "l", "lizard":      choice = .lizard    case "spock":      choice = .spock    case "q", "quit", "exit":      break loop    case "s":      print("Do you mean Spock, or scissors?")      continue    default:       print("Unknown choice. Type 'q' to quit")      continue  }  let p2Choice = aiChoice(for: game)  print("You played \(choice) against \(p2Choice)")  game.play(choice, against: p2Choice)  print("Current score: \(game.p1Score) : \(game.p2Score)")}`

Sample run:

```Type your choice to play a round, or 'q' to quit
r
You played rock against paper
Current score: 0 : 1
Paper
You played paper against paper
Current score: 0 : 1
spock
You played spock against lizard
Current score: 0 : 2
lizard
You played lizard against paper
Current score: 1 : 2
q
```

## Tcl

`package require Tcl 8.5 ### Choices are represented by integers, which are indices into this list:###    Rock, Paper, Scissors### Normally, idiomatic Tcl code uses names for these sorts of things, but it### turns out that using integers simplifies the move-comparison logic. # How to ask for a move from the human playerproc getHumanMove {} {    while 1 {	puts -nonewline "Your move? \[R\]ock, \[P\]aper, \[S\]cissors: "	flush stdout	gets stdin line	if {[eof stdin]} {	    puts "\nBye!"	    exit	}	set len [string length \$line]	foreach play {0 1 2} name {"rock" "paper" "scissors"} {	    # Do a prefix comparison	    if {\$len && [string equal -nocase -length \$len \$line \$name]} {		return \$play	    }	}	puts "Sorry, I don't understand that. Try again please."    }} # How to ask for a move from the machine playerproc getMachineMove {} {    global states    set choice [expr {int(rand() * [::tcl::mathop::+ {*}\$states 3])}]    foreach play {1 2 0} count \$states {	if {[incr sum [expr {\$count+1}]] > \$choice} {	    puts "I play \"[lindex {Rock Paper Scissors} \$play]\""	    return \$play	}    }} # Initialize some state variablesset states {0 0 0}set humanWins 0set machineWins 0 # The main game loopwhile 1 {    # Get the moves for this round    set machineMove [getMachineMove]    set humanMove [getHumanMove]    # Report on what happened    if {\$humanMove == \$machineMove} {	puts "A draw!"    } elseif {(\$humanMove+1)%3 == \$machineMove} {	puts "I win!"	incr machineWins    } else {	puts "You win!"	incr humanWins    }    puts "Cumulative scores: \$humanWins to you, \$machineWins to me"    # Update the state of how the human has played in the past    lset states \$humanMove [expr {[lindex \$states \$humanMove] + 1}]}`

Sample run:

```Your move? [R]ock, [P]aper, [S]cissors: rock
I play "Scissors"
You win!
Cumulative scores: 1 to you, 0 to me
Your move? [R]ock, [P]aper, [S]cissors: r
I play "Paper"
I win!
Cumulative scores: 1 to you, 1 to me
Your move? [R]ock, [P]aper, [S]cissors: s
I play "Paper"
You win!
Cumulative scores: 2 to you, 1 to me
Your move? [R]ock, [P]aper, [S]cissors: sciss
I play "Paper"
You win!
Cumulative scores: 3 to you, 1 to me
Your move? [R]ock, [P]aper, [S]cissors: p
I play "Paper"
A draw!
Cumulative scores: 3 to you, 1 to me
Your move? [R]ock, [P]aper, [S]cissors: zaphod beeblebrox
Sorry, I don't understand that. Try again please.
Your move? [R]ock, [P]aper, [S]cissors: r
I play "Scissors"
You win!
Cumulative scores: 4 to you, 1 to me
Your move? [R]ock, [P]aper, [S]cissors: ^D
Bye!
```

## TorqueScript

Rock Paper Scissors in TorqueScript:

` while(isobject(RockPaperScissors))	RockPaperScissors.delete(); new scriptObject(RockPaperScissors); function RockPaperScissors::startGame(%this){	%this.idle = true;	echo("Starting rock paper scissors, please type choose(\"choice\"); to proceed!");} function RockPaperScissors::endGame(%this){	%this.idle = true;} function RockPaperScissors::main(%this){	%this.idle = 0; 	if(getRandom(1,2) == 1)	{		%result = %this.getChoiceByUserFrequency();	}	else	{		%c[0] = "rock";		%c[1] = "paper";		%c[2] = "scissors"; 		%result = %c[getRandom(0,2)]; 	} 	%userChoice = %this.current; 	%winner = thisVSthat(%userChoice,%result); 	if(%winner == 0)	{		echo("You both chose "@%[email protected]", tie!");	}	else	if(%winner == 1)	{		echo("You chose "@%[email protected]" computer chose "@%[email protected]", you win!");	}	else	if(%winner == 2)	{		echo("You chose "@%[email protected]" computer chose "@%[email protected]", you lose!");	} 	%this.idle = true;} function RockPaperScissors::getChoiceByUserFrequency(%this){	%weakness["rock"] = "paper";	%weakness["paper"] = "Scissors";	%weakness["scissors"] = "rock"; 	%a[0] = %this.choice["rock"];	%a[1] = %this.choice["paper"];	%a[2] = %this.choice["Scissors"]; 	%b[0] = "rock";	%b[1] = "paper";	%b[2] = "scissors"; 	for(%i=0;%i<3;%i++)	{		%curr = %a[%i]; 		if(%temp \$= "")		{			%temp = %curr;			%tempi = %i;		}		else		if(%curr > %temp)		{			%temp = %curr;			%tempi = %i;		}	} 	return %weakness[%b[%tempi]];} function choose(%this){	%rps = rockPaperScissors; 	if(!%rps.idle)	{		return 0;	}	else	if(%this !\$= "rock" && %this !\$= "paper" && %this !\$= "scissors")	{		return 0;	} 	%rps.choice[%this]++;	%rps.current = %this;	%rps.main(); 	return %this;} function thisVSthat(%this,%that){	if(%this !\$= "rock" && %this !\$= "paper" && %this !\$= "scissors")	{		return 0;	}	else	if(%that !\$= "rock" && %that !\$= "paper" && %that !\$= "scissors")	{		return 0;	} 	%weakness["rock"] = "paper";	%weakness["paper"] = "Scissors";	%weakness["scissors"] = "rock"; 	if(%weakness[%this] \$= %that)	{		%result = 2;	}	else	if(%weakness[%that] \$= %this)	{		%result = 1;	}	else		%result = 0; 	return %result;} `

To begin do:

` RockPaperScissors.startGame(); `

Choose and play!

` choose("Rock"); `

=> You chose rock computer chose paper, you lose!

## TI-83 BASIC

`PROGRAM:RPS:{0,0,0}→L1:{0,0,0}→L2:Lbl ST:Disp "R/P/S":Disp "1/2/3":Lbl EC:Input A:If A>3 or A<1:Then:Goto NO:End:randInt(1,3+L1(1)+L1(2)+L1(3)→C:If C≤1+L1(1):Then:2→B:Goto NS:End:If C>2+L1(2):Then:1→B:Else:3→B:End:Lbl NS:L1(A)+1→L1(A):If A=B:Then:Disp "TIE GAME":L2(3)+1→L2(3):Goto TG:End:If (A=1 and B=2) or (A=2 and B=3) or (A=3 and B=1):Then:Disp "I WIN":L2(1)+1→L2(1):Else:Disp "YOU WIN":L2(2)+1→L2(2):End:Lbl TG:Disp "PLAY AGAIN?":Input Str1:If Str1="YES":Then:ClrHome:Goto ST:Else:Goto EN:End:Lbl NO:ClrHome:Pause "PICK 1,2, or 3":ClrHome:Goto EC:Lbl EN:ClrHome:Disp "I WON:":Disp L2(1):Disp "YOU WON:":Disp L2(2):Disp "WE TIED:":Disp L2(3):Disp "BYE" `

## uBasic/4tH

This implementation uses a 6-bits binary scheme, where the lower three bits represent the choice of the user and the higher three bits the choice of the computer:

 This example is incorrect. Please fix the code and remove this message.Details: This example does not seem to use the weighted average AI from the task description.
` 20 LET P=0: LET Q=0: LET Z=0 30 INPUT "Rock, paper, or scissors (1 = rock, 2 = paper, 3 = scissors)? ", A 40 IF A>3 THEN GOTO 400 50 IF A=3 THEN LET A=4 60 IF A<1 THEN GOTO 400 70 C=RND(3) : LET D=4: FOR B=1 TO C+1 : LET D = D+D : NEXT : GOTO (A+D)*10 90 Z=Z+1 : PRINT "We both chose 'rock'. It's a draw." : GOTO 30100 P=P+1 : PRINT "You chose 'paper', I chose 'rock'. You win.." : GOTO 30120 Q=Q+1 : PRINT "You chose 'scissors', I chose 'rock'. I win!" : GOTO 30170 Q=Q+1 : PRINT "You chose 'rock', I chose 'paper'. I win!" : GOTO 30180 Z=Z+1 : PRINT "We both chose 'paper'. It's a draw." : GOTO 30200 P=P+1 : PRINT "You chose 'scissors', I chose 'paper'. You win.." : GOTO 30330 P=P+1 : PRINT "You chose 'rock', I chose 'scissors'. You win.." : GOTO 30340 Q=Q+1 : PRINT "You chose 'paper', I chose 'scissors'. I win!" : GOTO 30360 Z=Z+1 : PRINT "We both chose 'scissors'. It's a draw." : GOTO 30400 PRINT "There were ";Z;" draws. I lost ";P;" times, you lost ";Q;" times." : END`

A sample game:

```Rock, paper, or scissors (1 = rock, 2 = paper, 3 = scissors)? 1
You chose 'rock', I chose 'paper'. I win!
Rock, paper, or scissors (1 = rock, 2 = paper, 3 = scissors)? 2
You chose 'paper', I chose 'scissors'. I win!
Rock, paper, or scissors (1 = rock, 2 = paper, 3 = scissors)? 3
You chose 'scissors', I chose 'paper'. You win..
Rock, paper, or scissors (1 = rock, 2 = paper, 3 = scissors)? 1
You chose 'rock', I chose 'paper'. I win!
Rock, paper, or scissors (1 = rock, 2 = paper, 3 = scissors)? 2
We both chose 'paper'. It's a draw.
Rock, paper, or scissors (1 = rock, 2 = paper, 3 = scissors)? 3
You chose 'scissors', I chose 'rock'. I win!
Rock, paper, or scissors (1 = rock, 2 = paper, 3 = scissors)? 4
There were 1 draws. I lost 1 times, you lost 4 times.
```

## UNIX Shell

Works with: Bourne Again Shell version 4
`#!/bin/bashchoices=(rock paper scissors) # comparison function, works like Perl # winner x y =  2 if y beats x, 1 if x beats 1, 0 if it's a tiewinner() {  local left="\$1" right="\$2"  echo \$(( (3 + left - right) % 3 ))}  human_counts=(1 1 1)human_count=3computer_counts=(0 0 0)games=0 human=0 computer=0 PS3="What do you throw? "while true; do   select choice in rock paper scissors quit; do    if [ -z "\$choice" ]; then choice="\$REPLY"; fi    if [ "\$choice" = "quit" ]; then      break 2    fi    for (( h=0; h<\${#choices[@]}; ++h )); do      if [ "\${choices[h]}" = "\$choice" ]; then        break      fi    done    if (( h < 3 )); then      break    fi    echo "Unrecognized choice.  Try again!"  done   let n=RANDOM%human_count  for (( c=0; c<\${#human_counts[@]}; ++c )); do    let n-=\${human_counts[c]}    if (( n < 0 )); then       break    fi  done  let computer_counts[c]+=1  echo   echo "You chose \${choices[h]^^}"  echo "I chose \${choices[c]^^}"  w="\$(winner "\$c" "\$h")"  case "\$w" in     2) echo "YOU WIN!"; let human+=1;;     0) echo "TIE!";;     1) echo "I WIN!"; let computer+=1;;     *) echo "winner returned weird result '\$w'";;  esac  echo  let games+=1  (( human_counts[(h+1)%3]+=1, human_count+=1 ))done echo echo "We played \$games games.  You won \$human, and I won \$computer."for (( i=0; i<3; ++i )); do  echo "You picked \${choices[i]} \$(( human_counts[ (i+1)%3 ] - 1 )) times."  echo "I picked \${choices[i]} \$(( computer_counts[i] )) times."done`

## Yabasic

`REM Yabasic 2.763 version WINNER = 1 : ACTION = 2 : LOSSER = 3dim word\$(10, 3) for n = 0 to 9    read word\$(n, WINNER), word\$(n, ACTION), word\$(n, LOSSER)next n repeat    clear screen    computerChoice\$ = word\$(ran(10), WINNER)    print "'Rock, Paper, Scissors, Lizard, Spock!' rules are:\n"    for n = 0 to 9        SimonSay(n)    next n    print "\nType your choice letter:"    print "(R)ock, (P)aper, (S)cissors, (L)izard, Spoc(K), (Q)uit\n"    k\$ = upper\$(inkey\$)    if k\$ = "Q" break    switch k\$        case "R": humanChoice\$ = "Rock" : break        case "P": humanChoice\$ = "Paper" : break        case "S": humanChoice\$ = "Scissors" : break        case "L": humanChoice\$ = "Lizard" : break        case "K": humanChoice\$ = "Spock" : break        end switch    print "Player chose ", humanChoice\$, " and Computer chose ", computerChoice\$    for n = 0 to 9        if word\$(n, WINNER) = humanChoice\$ and word\$(n, LOSSER) = computerChoice\$ then            SimonSay(n)            print "Winner was Player"            wp = wp + 1            break        elseif word\$(n, WINNER) = computerChoice\$ and word\$(n, LOSSER) = humanChoice\$ then            SimonSay(n)            print "Winner was Computer"            wc = wc + 1            break        end if        next n    if n = 10 then        print "Ouch!"    end if    punctuation()    print "\nPress any key to continue"    inkey\$until(k\$ = "Q") punctuation()if wp > wc then    print "Player win"elseif wc > wp then    print "Computer win"else    print "Tie"end if end sub SimonSay(n)    print word\$(n, WINNER), " ", word\$(n, ACTION), " ", word\$(n, LOSSER)end sub sub punctuation()    print "\nPlayer = ", wp, "\tComputer = ", wc, "\n"end sub data "Scissors","cuts","Paper"data "Paper","covers","Rock"data "Rock","crushes","Lizard"data "Lizard","poisons","Spock"data "Spock","smashes","Scissors"data "Scissors","decapites","Lizard"data "Lizard","eats","Paper"data "Paper","disproves","Spock"data "Spock","vaporizes","Rock"data "Rock","blunts","Scissors"`