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Tic-tac-toe

From Rosetta Code
(Redirected from Noughts and crosses)
Task
Tic-tac-toe
You are encouraged to solve this task according to the task description, using any language you may know.
Tic tac toe.jpg
Task

Play a game of tic-tac-toe.

Ensure that legal moves are played and that a winning position is notified.


Tic-tac-toe   is also known as:

  •   naughts and crosses
  •   tic tac toe
  •   tick tack toe
  •   three in a row
  •   tres en rayo       and
  •   Xs  and  Os


See also



11l[edit]

Translation of: Python
UInt32 seed = 0
F nonrandom_choice(lst)
 :seed = 1664525 * :seed + 1013904223
R lst[:seed % UInt32(lst.len)]
 
V board = Array(‘123456789’)
V wins = ([0, 1, 2], [3, 4, 5], [6, 7, 8],
[0, 3, 6], [1, 4, 7], [2, 5, 8],
[0, 4, 8], [2, 4, 6])
 
F printboard()
print([0, 3, 6].map(x -> (:board[x .+ 3]).join(‘ ’)).join("\n"))
 
F score(board = board) -> (Char, [Int])?
L(w) :wins
V b = board[w[0]]
I b C ‘XO’ & all(w.map(i -> @board[i] == @b))
R (b, w.map(i -> i + 1))
R N
 
F finished()
R all(:board.map(b -> b C ‘XO’))
 
F space(board = board)
R board.filter(b -> b !C ‘XO’)
 
F my_turn(xo, &board)
V options = space()
V choice = nonrandom_choice(options)
board[Int(choice) - 1] = xo
R choice
 
F my_better_turn(xo, &board)
‘Will return a next winning move or block your winning move if possible’
V ox = I xo == ‘X’ {Char(‘O’)} E Char(‘X’)
Int? oneblock
V options = space(board).map(s -> Int(s) - 1)
Int choice
L(chc) options
V brd = copy(board)
brd[chc] = xo
I score(brd) != N
choice = chc
L.break
I oneblock == N
brd[chc] = ox
I score(brd) != N
oneblock = chc
L.was_no_break
choice = oneblock ? nonrandom_choice(options)
board[choice] = xo
R choice + 1
 
F your_turn(xo, &board)
V options = space()
L
V choice = input("\nPut your #. in any of these positions: #. ".format(xo, options.join(‘’))).trim((‘ ’, "\t", "\r", "\n"))
I choice C options
board[Int(choice) - 1] = xo
R choice
print(‘Whoops I don't understand the input’)
 
F me(xo = Char(‘X’))
printboard()
print("\nI go at "my_better_turn(xo, &:board))
R score()
 
F you(xo = Char(‘O’))
printboard()
print("\nYou went at "my_turn(xo, &:board))
R score()
 
L !finished()
(Char, [Int])? s = me(Char(‘X’))
I s != N
printboard()
print("\n#. wins along #.".format(s[0], s[1]))
L.break
I !finished()
s = you(Char(‘O’))
I s != N
printboard()
print("\n#. wins along #.".format(s[0], s[1]))
L.break
L.was_no_break
print("\nA draw")
Output:
1 2 3
4 5 6
7 8 9

I go at 8
1 2 3
4 5 6
7 X 9

You went at 3
1 2 O
4 5 6
7 X 9

I go at 1
X 2 O
4 5 6
7 X 9

You went at 5
X 2 O
4 O 6
7 X 9

I go at 7
X 2 O
4 O 6
X X 9

You went at 9
X 2 O
4 O 6
X X O

I go at 4
X 2 O
X O 6
X X O

X wins along [1, 4, 7]

Ada[edit]

with Ada.Text_IO, Ada.Numerics.Discrete_Random;
-- can play human-human, human-computer, computer-human or computer-computer
-- the computer isn't very clever: it just chooses a legal random move
 
procedure Tic_Tac_Toe is
 
type The_Range is range 1 .. 3;
type Board_Type is array (The_Range, The_Range) of Character;
 
package Rand is new Ada.Numerics.Discrete_Random(The_Range);
Gen: Rand.Generator; -- required for the random moves
 
procedure Show_Board(Board: Board_Type) is
use Ada.Text_IO;
begin
for Row in The_Range loop
for Column in The_Range loop
Put(Board(Row, Column));
end loop;
Put_Line("");
end loop;
Put_Line("");
end Show_Board;
 
function Find_Winner(Board: Board_Type) return Character is
-- if 'x' or 'o' wins, it returns that, else it returns ' '
 
function Three_Equal(A,B,C: Character) return Boolean is
begin
return (A=B) and (A=C);
end Three_Equal;
 
begin -- Find_Winner
for I in The_Range loop
if Three_Equal(Board(I,1), Board(I,2), Board(I,3)) then
return Board(I,1);
elsif Three_Equal(Board(1,I), Board(2,I), Board(3,I)) then
return Board(1,I);
end if;
end loop;
if Three_Equal(Board(1,1), Board(2,2), Board (3,3)) or
Three_Equal(Board(3,1), Board(2,2), Board (1,3)) then
return Board(2,2);
end if;
return ' ';
end Find_Winner;
 
procedure Do_Move(Board: in out Board_Type;
New_Char: Character; Computer_Move: Boolean) is
Done: Boolean := False;
C: Character;
use Ada.Text_IO;
 
procedure Do_C_Move(Board: in out Board_Type; New_Char: Character) is
Found: Boolean := False;
X,Y: The_Range;
begin
while not Found loop
X := Rand.Random(Gen);
Y := Rand.Random(Gen);
if (Board(X,Y) /= 'x') and (Board(X,Y) /= 'o') then
Found := True;
Board(X,Y) := New_Char;
end if;
end loop;
end Do_C_Move;
 
begin
if Computer_Move then
Do_C_Move(Board, New_Char);
else -- read move;
Put_Line("Choose your move, " & New_Char);
while not Done loop
Get(C);
for Row in The_Range loop
for Col in The_Range loop
if Board(Row, Col) = C then
Board(Row, Col) := New_Char;
Done := True;
end if;
end loop;
end loop;
end loop;
end if;
end Do_Move;
 
The_Board : Board_Type := (('1','2','3'), ('4','5','6'), ('7','8','9'));
Cnt_Moves: Natural := 0;
Players: array(0 .. 1) of Character := ('x', 'o'); -- 'x' begins
C_Player: array(0 .. 1) of Boolean := (False, False);
Reply: Character;
 
begin -- Tic_Tac_Toe
 
-- firstly, ask whether the computer shall take over either player
for I in Players'Range loop
Ada.Text_IO.Put_Line("Shall " & Players(I) &
" be run by the computer? (y=yes)");
Ada.Text_IO.Get(Reply);
if Reply='y' or Reply='Y' then
C_Player(I) := True;
Ada.Text_IO.Put_Line("Yes!");
else
Ada.Text_IO.Put_Line("No!");
end if;
end loop;
Rand.Reset(Gen); -- to initalize the random generator
 
-- now run the game
while (Find_Winner(The_Board) = ' ') and (Cnt_Moves < 9) loop
Show_Board(The_Board);
Do_Move(The_Board, Players(Cnt_Moves mod 2), C_Player(Cnt_Moves mod 2));
Cnt_Moves := Cnt_Moves + 1;
end loop;
Ada.Text_IO.Put_Line("This is the end!");
 
-- finally, output the outcome
Show_Board (The_Board);
if Find_Winner(The_Board) = ' ' then
Ada.Text_IO.Put_Line("Draw");
else
Ada.Text_IO.Put_Line("The winner is: " & Find_Winner(The_Board));
end if;
end Tic_Tac_Toe;
Output:
> ./tic_tac_toe 
Shall x be run by the computer? (y=yes)
y
Yes!
Shall o be run by the computer? (y=yes)
n
No!
123
456
789

1x3
456
789

Choose your move, o
5
1x3
4o6
789

1x3
xo6
789

Choose your move, o
6
1x3
xoo
789

1xx
xoo
789

Choose your move, o
1
oxx
xoo
789

oxx
xoo
78x

Choose your move, o
7
oxx
xoo
o8x

This is the end!
oxx
xoo
oxx

Draw

> ./tic_tac_toe 
Shall x be run by the computer? (y=yes)
n
No!
Shall o be run by the computer? (y=yes)
y
Yes!
123
456
789

Choose your move, x
6
123
45x
789

123
45x
o89

Choose your move, x
4
123
x5x
o89

123
x5x
o8o

Choose your move, x
8
123
x5x
oxo

o23
x5x
oxo

Choose your move, x
5
This is the end!
o23
xxx
oxo

The winner is: x

ALGOL W[edit]

The user can play O, X, both or neither. O goes first whether user or computer controlled.

begin
 
string(10) board;
 
 % initialise the board  %
procedure initBoard ; board := " 123456789";
 
 % display the board  %
procedure showBoard ;
begin
s_w := 0;
write( board(1//1), "|", board(2//1), "|", board(3//1) );
write( "-+-+-" );
write( board(4//1), "|", board(5//1), "|", board(6//1) );
write( "-+-+-" );
write( board(7//1), "|", board(8//1), "|", board(9//1) )
end showBoard ;
 
 % returns true if board pos is free, false otherwise  %
logical procedure freeSpace( integer value pos ) ;
( board(pos//1) >= "1" and board(pos//1) <= "9" );
 
 % check for game over  %
logical procedure gameOver ;
begin
logical noMoves;
noMoves := true;
for i := 1 until 9 do if noMoves then noMoves := not freeSpace( i );
noMoves
end gameOver ;
 
 % makes the specified winning move or blocks it, if it will win  %
logical procedure winOrBlock( integer value pos1, pos2, pos3
 ; string(1) value searchCharacter
 ; string(1) value playerCharacter
) ;
if board(pos1//1) = searchCharacter
and board(pos2//1) = searchCharacter
and freeSpace( pos3 )
then begin
board(pos3//1) := playerCharacter;
true
end
else if board(pos1//1) = searchCharacter
and freeSpace( pos2 )
and board(pos3//1) = searchCharacter
then begin
board(pos2//1) := playerCharacter;
true
end
else if freeSpace( pos1 )
and board(pos2//1) = searchCharacter
and board(pos3//1) = searchCharacter
then begin
board(pos1//1) := playerCharacter;
true
end
else begin
false
end winOrBlock ;
 
 % makes a winning move or blocks a winning move, if there is one  %
logical procedure makeOrBlockWinningMove( string(1) value searchCharacter
 ; string(1) value playerCharacter
) ;
( winOrBlock( 1, 2, 3, searchCharacter, playerCharacter )
or winOrBlock( 4, 5, 6, searchCharacter, playerCharacter )
or winOrBlock( 7, 8, 9, searchCharacter, playerCharacter )
or winOrBlock( 1, 4, 7, searchCharacter, playerCharacter )
or winOrBlock( 2, 5, 8, searchCharacter, playerCharacter )
or winOrBlock( 3, 6, 9, searchCharacter, playerCharacter )
or winOrBlock( 1, 5, 9, searchCharacter, playerCharacter )
or winOrBlock( 3, 5, 7, searchCharacter, playerCharacter )
) ;
 
 % makes a move when there isn't an obvious winning/blocking move  %
procedure move ( string(1) value playerCharacter ) ;
begin
logical moved;
moved := false;
 % try for the centre, a corner or the midle of a line  %
for pos := 5, 1, 3, 7, 9, 2, 4, 6, 8 do begin
if not moved and freeSpace( pos ) then begin
moved := true;
board(pos//1) := playerCharacter
end
end
end move ;
 
 % gets a move from the user  %
procedure userMove( string(1) value playerCharacter ) ;
begin
integer move;
while
begin
write( "Please enter the move for ", playerCharacter, " " );
read( move );
( move < 1 or move > 9 or not freeSpace( move ) )
end
do begin
write( "Invalid move" )
end;
board(move//1) := playerCharacter
end userMove ;
 
 % returns true if the three board positions have the player character,  %
 % false otherwise  %
logical procedure same( integer value pos1, pos2, pos3
 ; string(1) value playerCharacter
) ;
( board(pos1//1) = playerCharacter
and board(pos2//1) = playerCharacter
and board(pos3//1) = playerCharacter
);
 
 % returns true if the player has made a winning move, false otherwise  %
logical procedure playerHasWon( string(1) value playerCharacter ) ;
( same( 1, 2, 3, playerCharacter )
or same( 4, 5, 6, playerCharacter )
or same( 7, 8, 9, playerCharacter )
or same( 1, 4, 7, playerCharacter )
or same( 2, 5, 8, playerCharacter )
or same( 3, 6, 9, playerCharacter )
or same( 1, 5, 9, playerCharacter )
or same( 3, 5, 7, playerCharacter )
) ;
 
 % takes a players turn - either automated or user input  %
procedure turn ( string(1) value playerCharacter, otherCharacter
 ; logical value playerIsUser
) ;
begin
if playerIsUser then userMove( playerCharacter )
else begin
write( playerCharacter, " moves..." );
if not makeOrBlockWinningMove( playerCharacter, playerCharacter )
and not makeOrBlockWinningMove( otherCharacter, playerCharacter )
then move( playerCharacter )
end;
showBoard
end turn ;
 
 % asks a question and returns true if the user inputs y/Y,  %
 % false otherwise  %
logical procedure yes( string(32) value question ) ;
begin
string(1) answer;
write( question );
read( answer );
answer = "y" or answer = "Y"
end yes ;
 
 % play the game  %
while
begin
string(1) again;
string(32) gameResult;
logical oIsUser, xIsUser;
 
oIsUser := yes( "Do you want to play O? " );
xIsUser := yes( "Do you want to play X? " );
 
gameResult := "it's a draw";
initBoard;
showBoard;
while not gameOver and not playerHasWon( "O" ) and not playerHasWon( "X" ) do begin
turn( "O", "X", oIsUser );
if playerHasWon( "O" ) then gameResult := "O wins"
else if not gameOver then begin
turn( "X", "O", xIsUser );
if playerHasWon( "X" ) then gameResult := "X wins"
end
end ;
write( gameResult );
 
yes( "Play again? " )
end
do begin end
 
end.
Output:
Do you want to play O?          y
Do you want to play X?          n
1|2|3
-+-+-
4|5|6
-+-+-
7|8|9
Please enter the move for O 5
1|2|3
-+-+-
4|O|6
-+-+-
7|8|9
X moves...
X|2|3
-+-+-
4|O|6
-+-+-
7|8|9
...etc...
Please enter the move for O 8
X|2|O
-+-+-
O|O|X
-+-+-
X|O|9
X moves...
X|X|O
-+-+-
O|O|X
-+-+-
X|O|9
Please enter the move for O 9
X|X|O
-+-+-
O|O|X
-+-+-
X|O|O
it's a draw                     
Play again?                     n

AppleScript[edit]

property OMask : missing value
property XMask : missing value
property winningNumbers : {7, 56, 73, 84, 146, 273, 292, 448}
property difficulty : missing value
 
repeat
set OMask to 0
set XMask to 0
 
if button returned of (display dialog "Who should start?" buttons {"I shoud", "CPU"}) = "CPU" then set OMask to npcGet()
set difficulty to button returned of (display dialog "Please choose your difficulty" buttons {"Hard", "Normal"})
 
repeat
set XMask to XMask + 2 ^ (nGet() - 1)
if winnerForMask(XMask) or OMask + XMask = 511 then exit repeat
set OMask to npcGet()
if winnerForMask(OMask) or OMask + XMask = 511 then exit repeat
end repeat
 
if winnerForMask(OMask) then
set msg to "CPU Wins!"
else if winnerForMask(XMask) then
set msg to "You WON!!!"
else
set msg to "It's a draw"
end if
 
display dialog msg & return & return & drawGrid() & return & return & "Do you want to play again?"
end repeat
 
on nGet()
set theMessage to "It's your turn Player 1, please fill in the number for X" & return & return & drawGrid()
repeat
set value to text returned of (display dialog theMessage default answer "")
if (offset of value in "123456789") is not 0 then
if not positionIsUsed(value as integer) then exit repeat
end if
end repeat
return value as integer
end nGet
 
on npcGet()
--first get the free positions
set freeSpots to {}
repeat with s from 1 to 9
if not positionIsUsed(s) then set end of freeSpots to 2 ^ (s - 1)
end repeat
--second check if 1 move can make the CPU win
repeat with spot in freeSpots
if winnerForMask(OMask + spot) then return OMask + spot
end repeat
 
if difficulty is "Hard" and OMask is 0 then
if XMask = 1 or XMask = 4 then return 2
if XMask = 64 or XMask = 256 then return 128
end if
--third check if a user can make make it win (defensive) place it on position
repeat with spot in freeSpots
if winnerForMask(XMask + spot) then return OMask + spot
end repeat
 
--fourth check if CPU can win in two moves
repeat with spot1 in freeSpots
repeat with spot2 in freeSpots
if winnerForMask(OMask + spot1 + spot2) then return OMask + spot2
end repeat
end repeat
--fifth check if player can win in two moves
repeat with spot1 in freeSpots
repeat with spot2 in reverse of freeSpots
if winnerForMask(XMask + spot1 + spot2) then return OMask + spot1
end repeat
end repeat
--at last pick a random spot
if XMask + OMask = 0 and difficulty = "Hard" then return 1
 
return OMask + (some item of freeSpots)
end npcGet
 
on winnerForMask(mask)
repeat with winLine in winningNumbers
if BWAND(winLine, mask) = contents of winLine then return true
end repeat
return false
end winnerForMask
 
on drawGrid()
set grid to ""
repeat with o from 0 to 8
if BWAND(OMask, 2 ^ o) = 2 ^ o then
set grid to grid & "O"
else if BWAND(XMask, 2 ^ o) = 2 ^ o then
set grid to grid & "X"
else
set grid to grid & o + 1
end if
if o is in {2, 5} then set grid to grid & return
end repeat
return grid
end drawGrid
 
on positionIsUsed(pos)
return BWAND(OMask + XMask, 2 ^ (pos - 1)) = 2 ^ (pos - 1)
end positionIsUsed
 
on BWAND(n1, n2)
set theResult to 0
repeat with o from 0 to 8
if (n1 mod 2) = 1 and (n2 mod 2) = 1 then set theResult to theResult + 2 ^ o
set {n1, n2} to {n1 div 2, n2 div 2}
end repeat
return theResult as integer
end BWAND

AutoHotkey[edit]

This program uses a Gui with 9 buttons. Clicking on one will place an X there, disable the button, and cause the program to go somewhere. It plays logically, trying to win, trying to block, or playing randomly in that order.

Gui, Add, Button, x12 y12 w30 h30 vB1 gButtonHandler,
Gui, Add, Button, x52 y12 w30 h30 vB2 gButtonHandler,
Gui, Add, Button, x92 y12 w30 h30 vB3 gButtonHandler,
Gui, Add, Button, x12 y52 w30 h30 vB4 gButtonHandler,
Gui, Add, Button, x52 y52 w30 h30 vB5 gButtonHandler,
Gui, Add, Button, x92 y52 w30 h30 vB6 gButtonHandler,
Gui, Add, Button, x12 y92 w30 h30 vB7 gButtonHandler,
Gui, Add, Button, x52 y92 w30 h30 vB8 gButtonHandler,
Gui, Add, Button, x92 y92 w30 h30 vB9 gButtonHandler,
; Generated using SmartGUI Creator 4.0
Gui, Show, x127 y87 h150 w141, Tic-Tac-Toe
Winning_Moves := "123,456,789,147,258,369,159,357"
Return
 
ButtonHandler:
; Fired whenever the user clicks on an enabled button
Go(A_GuiControl,"X")
GoSub MyMove
Return
 
MyMove: ; Loops through winning moves. First attempts to win, then to block, then a random move
Went=0
Loop, parse, Winning_Moves,`,
{
Current_Set := A_LoopField
X:=O:=0
Loop, parse, Current_Set
{
GuiControlGet, Char,,Button%A_LoopField%
If ( Char = "O" )
O++
If ( Char = "X" )
X++
}
If ( O = 2 and X = 0 ) or ( X = 2 and O = 0 ){
Finish_Line(Current_Set)
Went = 1
Break ; out of the Winning_Moves Loop to ensure the computer goes only once
}
}
If (!Went)
GoSub RandomMove
Return
 
Go(Control,chr){
GuiControl,,%Control%, %chr%
GuiControl,Disable,%Control%
GoSub, CheckWin
}
 
CheckWin:
Loop, parse, Winning_Moves,`,
{
Current_Set := A_LoopField
X:=O:=0
Loop, parse, Current_Set
{
GuiControlGet, Char,,Button%A_LoopField%
If ( Char = "O" )
O++
If ( Char = "X" )
X++
}
If ( O = 3 ){
Msgbox O Wins!
GoSub DisableAll
Break
}
If ( X = 3 ){
MsgBox X Wins!
GoSub DisableAll
Break
}
}
return
 
DisableAll:
Loop, 9
GuiControl, Disable, Button%A_Index%
return
 
Finish_Line(Set){ ; Finish_Line is called when a line exists with 2 of the same character. It goes in the remaining spot, thereby blocking or winning.
Loop, parse, set
{
GuiControlGet, IsEnabled, Enabled, Button%A_LoopField%
Control=Button%A_LoopField%
If IsEnabled
Go(Control,"O")
}
}
 
RandomMove:
Loop{
Random, rnd, 1, 9
GuiControlGet, IsEnabled, Enabled, Button%rnd%
If IsEnabled
{
Control=Button%rnd%
Go(Control,"O")
Break
}
}
return
 
GuiClose:
ExitApp
 

AWK[edit]

 
# syntax: GAWK -f TIC-TAC-TOE.AWK
BEGIN {
move[12] = "3 7 4 6 8"; move[13] = "2 8 6 4 7"; move[14] = "7 3 2 8 6"
move[16] = "8 2 3 7 4"; move[17] = "4 6 8 2 3"; move[18] = "6 4 7 3 2"
move[19] = "8 2 3 7 4"; move[23] = "1 9 6 4 8"; move[24] = "1 9 3 7 8"
move[25] = "8 3 7 4 0"; move[26] = "3 7 1 9 8"; move[27] = "6 4 1 9 8"
move[28] = "1 9 7 3 4"; move[29] = "4 6 3 7 8"; move[35] = "7 4 6 8 2"
move[45] = "6 7 3 2 0"; move[56] = "4 7 3 2 8"; move[57] = "3 2 8 4 6"
move[58] = "2 3 7 4 6"; move[59] = "3 2 8 4 6"
split("7 4 1 8 5 2 9 6 3",rotate)
n = split("253 280 457 254 257 350 452 453 570 590",special)
i = 0
while (i < 9) { s[++i] = " " }
print("")
print("You move first, use the keypad:")
board = "\n7 * 8 * 9\n*********\n4 * 5 * 6\n*********\n1 * 2 * 3\n\n? "
printf(board)
}
state < 7 {
x = $0
if (s[x] != " ") {
printf("? ")
next
}
s[x] = "X"
++state
print("")
if (state > 1) {
for (i=0; i<r; ++i) { x = rotate[x] }
}
}
state == 1 {
for (r=0; x>2 && x!=5; ++r) { x = rotate[x] }
k = x
if (x == 5) { d = 1 } else { d = 5 }
}
state == 2 {
c = 5.5 * (k + x) - 4.5 * abs(k - x)
split(move[c],t)
d = t[1]
e = t[2]
f = t[3]
g = t[4]
h = t[5]
}
state == 3 {
k = x / 2.
c = c * 10
d = f
if (abs(c-350) == 100) {
if (x != 9) { d = 10 - x }
if (int(k) == k) { g = f }
h = 10 - g
if (x+0 == e+0) {
h = g
g = 9
}
}
else if (x+0 != e+0) {
d = e
state = 6
}
}
state == 4 {
if (x+0 == g+0) {
d = h
}
else {
d = g
state = 6
}
x = 6
for (i=1; i<=n; ++i) {
b = special[i]
if (b == 254) { x = 4 }
if (k+0 == abs(b-c-k)) { state = x }
}
}
state < 7 {
if (state != 5) {
for (i=0; i<4-r; ++i) { d = rotate[d] }
s[d] = "O"
}
for (b=7; b>0; b-=5) {
printf("%s * %s * %s\n",s[b++],s[b++],s[b])
if (b > 3) { print("*********") }
}
print("")
}
state < 5 {
printf("? ")
}
state == 5 {
printf("tie game")
state = 7
}
state == 6 {
printf("you lost")
state = 7
}
state == 7 {
printf(", play again? ")
++state
next
}
state == 8 {
if ($1 !~ /^[yY]$/) { exit(0) }
i = 0
while (i < 9) { s[++i] = " " }
printf(board)
state = 0
}
function abs(x) { if (x >= 0) { return x } else { return -x } }
 

Bash[edit]

Computer is X. Computer randomly goes first. Computer plays a good game, but not a perfect game. It will win when it can and draw when it can not.

It performs a depth-first scan of all following moves. It ignores dumb actions like not winning when either player can.

For each possible move it records if it will win, lose, or something else (like win and draw depending on opponent's move).

If there is a choice of best moves, it picks one at random.

I have not used simple bash code to:

  1. keep it under 100 lines;
  2. to demonstrate usefulness of bash integers;
  3. show-off ANSI ESC sequences;
  4. implement recursion in bash;
  5. demonstrate conditional and alternate execution using && and || with { ...; };
  6. show that you don't always need to use $ to refer to integer variables;
  7. encourage use of [[ ]] instead of [ ] for boolean expressions;
  8. provide examples of pattern matching; and
  9. encourage use of bash for more interesting tasks.
 
#!/bin/bash
declare -a B=( e e e e e e e e e ) # Board
 
function show(){ # show B - underline first 2 rows; highlight position; number empty positoins
local -i p POS=${1:-9}; local UL BOLD="\e[1m" GREEN="\e[32m" DIM="\e[2m" OFF="\e[m" ULC="\e[4m"
for p in 0 1 2 3 4 5 6 7 8; do
[[ p%3 -eq 0 ]] && printf " " # indent boards
UL=""; [[ p/3 -lt 2 ]] && UL=$ULC # underline first 2 rows
[[ p -eq POS ]] && printf "$BOLD$GREEN" # bold and colour for this position
[[ ${B[p]} = e ]] && printf "$UL$DIM%d$OFF" $p || printf "$UL%s$OFF" ${B[p]} # num or UL
{ [[ p%3 -lt 2 ]] && printf "$UL | $OFF"; } || printf "\n" # underline vertical bars or NL
done
};
 
function win(){ # win 'X' 3 return true if X wins after move in position 3
local ME=$1; local -i p=$2
[[ ${B[p/3*3]} = $ME && ${B[p/3*3+1]} = $ME && ${B[p/3*3+2]} = $ME ]] && return 0 # row
[[ ${B[p]} = $ME && ${B[(p+3)%9]} = $ME && ${B[(p+6)%9]} = $ME ]] && return 0 # col
[[ ${B[4]} != $ME ]] && return 1 # don't test diags
[[ p%4 -eq 0 && ${B[0]} = $ME && ${B[8]} = $ME ]] && return 0 # TL - BR diag
[[ p%4 -eq 2 || p -eq 4 ]] && [[ ${B[2]} = $ME && ${B[6]} = $ME ]] # TR - BL diag
};
 
function bestMove(){ # return best move or 9 if none possible
local ME=$1 OP=$2; local -i o s p
local -ia S=( -9 -9 -9 -9 -9 -9 -9 -9 -9 ) # score board
local -a SB # save board
[[ ${B[*]//[!e]} = "" ]] && return 9 # game over
SB=( ${B[*]} ) # save Board
for p in 0 1 2 3 4 5 6 7 8; do # for each board position
[[ ${B[p]} != e ]] && continue # skip occupied positions
B[p]=$ME # occupy position
win $ME $p && { S[p]=2; B=( ${SB[*]} ); return $p; } # ME wins so this is best move
bestMove $OP $ME; o=$? # what will opponent do
[[ o -le 8 ]] && { B[o]=$OP; win $OP $o; s=$?; } # opponent can make a legal move
S[p]=${s:-1} # save result of opponent move
B=( ${SB[*]} ) # restore board after each trial run
done
local -i best=-1; local -ia MOV=()
for p in 0 1 2 3 4 5 6 7 8; do # find all best moves
[[ S[p] -lt 0 ]] && continue # dont bother with occupied positions
[[ S[p] -eq S[best] ]] && { MOV+=(p); best=p; } # add this move to current list
[[ S[p] -gt S[best] ]] && { MOV=(p); best=p; } # a better move so scrap list and start again
done
return ${MOV[ RANDOM%${#MOV[*]} ]} # pick one at random
};
 
function getMove(){ # getMove from opponent
[[ $ME = X ]] && { bestMove $ME $OP; return $?; } # pick X move automatically
read -p "O move: " -n 1; printf "\n"; return $REPLY # get opponents move
};
 
function turn(){ # turn starts or continues a game. It is ME's turn
local -i p; local ME=$1 OP=$2
getMove; p=$?; [[ p -gt 8 ]] && { printf "Draw!\n"; show; return 1; } # no move so a draw
B[p]=$ME; printf "%s moves %d\n" $ME $p # mark board
win $ME $p && { printf "%s wins!\n" $ME; show $p; [[ $ME = X ]] && return 2; return 0; }
[[ ${B[*]//[!e]} = "" ]] && { printf "Draw!\n"; show; return 1; } # no move so a draw
show $p; turn $OP $ME # opponent moves
};
 
printf "Bic Bash Bow\n"
show; [[ RANDOM%2 -eq 0 ]] && { turn O X; exit $?; } || turn X O
 
 
Output:
(nice ANSI formatting is not shown)
Bic Bash Bow
  0 | 1 | 2
  3 | 4 | 5
  6 | 7 | 8
X moves 1
  0 | X | 2
  3 | 4 | 5
  6 | 7 | 8
O move: 5
O moves 5
  0 | X | 2
  3 | 4 | O
  6 | 7 | 8
X moves 2
  0 | X | X
  3 | 4 | O
  6 | 7 | 8
O move: 0
O moves 0
  O | X | X
  3 | 4 | O
  6 | 7 | 8
X moves 4
  O | X | X
  3 | X | O
  6 | 7 | 8
O move: 6
O moves 6
  O | X | X
  3 | X | O
  O | 7 | 8
X moves 7
X wins!
  O | X | X
  3 | X | O
  O | X | 8

BASIC[edit]

BASIC256[edit]

 
# basado en código de Antonio Rodrigo dos Santos Silva (gracias):
# http://statusgear.freeforums.net/thread/17/basic-256-tic-tac-toe
 
global playerturn$
global endGame$
global space$
global player1Score$
global player2Score$
global invalidMove$
global tecla$
global keyQ$
global keyW$
global keyE$
global keyA$
global keyS$
global keyD$
global keyZ$
global keyX$
global keyC$
global keySpace$
global keyEsc$
 
keyQ$ = 81
keyW$ = 87
keyE$ = 69
keyA$ = 65
keyS$ = 83
keyD$ = 68
keyZ$ = 90
keyX$ = 88
keyC$ = 67
keySpace$ = 32
keyEsc$ = 16777216
 
dim space$(9)
 
 
subroutine clearGameVars()
playerturn$ = 1
invalidMove$ = 0
endGame$ = 0
tecla$ = 0
 
for t = 0 to space$[?]-1
space$[t] = 0
next t
end subroutine
 
subroutine endGame()
cls
print "¡Hasta pronto!..."
end
end subroutine
 
subroutine printBoard()
print " " + space$[0]+" | "+space$[1]+" | "+space$[2]
print " " + "— + — + —"
print " " + space$[3]+" | "+space$[4]+" | "+space$[5]
print " " + "— + — + —"
print " " + space$[6]+" | "+space$[7]+" | "+space$[8]
print ""
end subroutine
 
subroutine changePlayer()
if playerturn$ = 1 then
playerturn$ = 2
else
playerturn$ = 1
end if
end subroutine
 
subroutine endMatchWithWinner()
cls
call printPlayerScore()
call printBoard()
endGame$ = 1
 
if playerturn$ = 1 then
player1Score$ += 1
else
player2Score$ += 1
end if
 
print "¡Jugador " + playerturn$ + " gana!" + chr(10)
print "Pulsa [SPACE] para jugar otra partida"
print "Pulsa [ESC] para dejar de jugar"
do
tecla$ = key
pause .01
if tecla$ = keySpace$ then call gamePlay()
if tecla$ = keyEsc$ then call endGame()
until false
end subroutine
 
subroutine endMatchWithoutWinner()
cls
call printPlayerScore()
call printBoard()
endGame$ = 1
 
print " Nadie ganó :( " + chr(10)
print " Pulsa [SPACE] para comenzar o [ESC] para salir. "
do
tecla$ = key
pause .01
if tecla$ = keySpace$ then call gamePlay()
if tecla$ = keyEsc$ then call endGame()
until false
end subroutine
 
subroutine printPlayerScore()
print "--------------------------------------------"
print " Jugador #1: " + player1Score$ + " pts"
print " Jugador #2: " + player2Score$ + " pts"
print "--------------------------------------------" + chr(10)
end subroutine
 
 
subroutine printPlayerMessage()
print "Jugador: " + playerturn$ + ", elige una casilla, por favor."
end subroutine
 
subroutine gamePlay()
call clearGameVars()
cls
call printPlayerScore()
call printBoard()
call printPlayerMessage()
while 0 = 0
invalidMove$ = 0
 
if endGame$ = 0 then
do
tecla$ = key
pause .01
validKeypressed$ = 0
if tecla$ = keyQ$ or tecla$ = keyW$ or tecla$ = keyE$ or tecla$ = keyA$ or tecla$ = keyS$ or tecla$ = keyD$ or tecla$ = keyZ$ or tecla$ = keyX$ or tecla$ = keyC$ then validKeypressed$ = 1
until validKeypressed$ = 1
endif
 
if tecla$ = keyQ$ then
if space$[0] = 0 then
space$[0] = playerturn$
else
invalidMove$ = 1
endif
endif
 
if tecla$ = keyW$ then
if space$[1] = 0 then
space$[1] = playerturn$
else
invalidMove$ = 1
endif
endif
 
if tecla$ = keyE$ then
if space$[2] = 0 then
space$[2] = playerturn$
else
invalidMove$ = 1
endif
endif
 
if tecla$ = keyA$ then
if space$[3] = 0 then
space$[3] = playerturn$
else
invalidMove$ = 1
endif
endif
 
if tecla$ = keyS$ then
if space$[4] = 0 then
space$[4] = playerturn$
else
invalidMove$ = 1
endif
endif
 
if tecla$ = keyD$ then
if space$[5] = 0 then
space$[5] = playerturn$
else
invalidMove$ = 1
endif
endif
 
if tecla$ = keyZ$ then
if space$[6] = 0 then
space$[6] = playerturn$
else
invalidMove$ = 1
endif
endif
 
if tecla$ = keyX$ then
if space$[7] = 0 then
space$[7] = playerturn$
else
invalidMove$ = 1
endif
endif
 
if tecla$ = keyC$ then
if space$[8] = 0 then
space$[8] = playerturn$
else
invalidMove$ = 1
endif
endif
 
if invalidMove$ = 0 then
tecla$ = 0
 
if space$[0] = 1 and space$[1] = 1 and space$[2] = 1 then call endMatchWithWinner()
if space$[3] = 1 and space$[4] = 1 and space$[5] = 1 then call endMatchWithWinner()
if space$[6] = 1 and space$[7] = 1 and space$[8] = 1 then call endMatchWithWinner()
if space$[0] = 1 and space$[3] = 1 and space$[6] = 1 then call endMatchWithWinner()
if space$[1] = 1 and space$[4] = 1 and space$[7] = 1 then call endMatchWithWinner()
if space$[2] = 1 and space$[5] = 1 and space$[8] = 1 then call endMatchWithWinner()
if space$[0] = 1 and space$[4] = 1 and space$[8] = 1 then call endMatchWithWinner()
if space$[2] = 1 and space$[4] = 1 and space$[6] = 1 then call endMatchWithWinner()
if space$[0] = 2 and space$[1] = 2 and space$[2] = 2 then call endMatchWithWinner()
if space$[3] = 2 and space$[4] = 2 and space$[5] = 2 then call endMatchWithWinner()
if space$[6] = 2 and space$[7] = 2 and space$[8] = 2 then call endMatchWithWinner()
if space$[0] = 2 and space$[3] = 2 and space$[6] = 2 then call endMatchWithWinner()
if space$[1] = 2 and space$[4] = 2 and space$[7] = 2 then call endMatchWithWinner()
if space$[2] = 2 and space$[5] = 2 and space$[8] = 2 then call endMatchWithWinner()
if space$[0] = 2 and space$[4] = 2 and space$[8] = 2 then call endMatchWithWinner()
if space$[2] = 2 and space$[4] = 2 and space$[6] = 2 then call endMatchWithWinner()
 
if space$[0] <> 0 and space$[1] <> 0 and space$[2] <> 0 and space$[3] <> 0 and space$[4] <> 0 and space$[5] <> 0 and space$[6] <> 0 and space$[7] <> 0 and space$[8] <> 0 then call endMatchWithoutWinner()
 
call changePlayer()
cls
call printPlayerScore()
call printBoard()
call printPlayerMessage()
end if
 
end while
end subroutine
 
subroutine gameMenu()
cls
call clearGameVars()
 
player1Score$ = 0
player2Score$ = 0
 
print "================================================="
print "| TIC-TAC-TOE |"
print "=================================================" + chr(10)
print " Teclas para jugar:"
print "---------------------"
print " | q | w | e |"
print " | a | s | d |"
print " | z | x | c |" + chr(10)
print " Pulsa [SPACE] para comenzar o [ESC] para salir. "
 
do
tecla$ = key
pause .01
if tecla$ = keySpace$ then call gamePlay()
if tecla$ = keyEsc$ then call endGame()
until false
end subroutine
 
call gameMenu()
end
 


Microsoft Small Basic[edit]

This game has a simple AI.

place1 = 1
place2 = 2
place3 = 3
place4 = 4
place5 = 5
place6 = 6
place7 = 7
place8 = 8
place9 = 9
symbol1 = "X"
symbol2 = "O"
reset:
TextWindow.Clear()
TextWindow.Write(place1 + " ")
TextWindow.Write(place2 + " ")
TextWindow.WriteLine(place3 + " ")
TextWindow.Write(place4 + " ")
TextWindow.Write(place5 + " ")
TextWindow.WriteLine(place6 + " ")
TextWindow.Write(place7 + " ")
TextWindow.Write(place8 + " ")
TextWindow.WriteLine(place9 + " ")
TextWindow.WriteLine("Where would you like to go to (choose a number from 1 to 9 and press enter)?")
n = TextWindow.Read()
If n = 1 then
If place1 = symbol1 or place1 = symbol2 then
Goto ai
Else
place1 = symbol1
EndIf
ElseIf n = 2 then
If place2 = symbol1 or place2 = symbol2 then
Goto ai
Else
place2 = symbol1
EndIf
ElseIf n = 3 then
If place3 = symbol1 or place3 = symbol2 then
Goto ai
Else
place3 = symbol1
EndIf
ElseIf n = 4 then
If place4 = symbol1 or place4 = symbol2 then
Goto ai
Else
place4 = symbol1
EndIf
ElseIf n = 5 then
If place5 = symbol1 or place5 = symbol2 then
Goto ai
Else
place5 = symbol1
EndIf
ElseIf n = 6 then
If place6 = symbol1 or place6 = symbol2 then
Goto ai
Else
place6 = symbol1
EndIf
ElseIf n = 7 then
If place8 = symbol1 or place7 = symbol2 then
Goto ai
Else
place7 = symbol1
EndIf
ElseIf n = 8 then
If place8 = symbol1 or place8 = symbol2 then
Goto ai
Else
place8 = symbol1
EndIf
ElseIf n = 9 then
If place9 = symbol1 or place9 = symbol2 then
Goto ai
Else
place9 = symbol1
EndIf
EndIf
Goto ai
ai:
n = Math.GetRandomNumber(9)
If n = 1 then
If place1 = symbol1 or place1 = symbol2 then
Goto ai
Else
place1 = symbol2
EndIf
ElseIf n = 2 then
If place2 = symbol1 or place2 = symbol2 then
Goto ai
Else
place2 = symbol2
EndIf
ElseIf n = 3 then
If place3 = symbol1 or place3 = symbol2 then
Goto ai
Else
place3 = symbol2
EndIf
ElseIf n = 4 then
If place4 = symbol1 or place4 = symbol2 then
Goto ai
Else
place4 = symbol2
EndIf
ElseIf n = 5 then
If place5 = symbol1 or place5 = symbol2 then
Goto ai
Else
place5 = symbol2
EndIf
ElseIf n = 6 then
If place6 = symbol1 or place6 = symbol2 then
Goto ai
Else
place6 = symbol2
EndIf
ElseIf n = 7 then
If place7 = symbol1 or place7 = symbol2 then
Goto ai
Else
place7 = symbol2
EndIf
ElseIf n = 8 then
If place8 = symbol1 or place8 = symbol2 then
Goto ai
Else
place8 = symbol2
EndIf
ElseIf n = 9 then
If place9 = symbol1 or place9 = symbol2 then
Goto ai
Else
place9 = symbol2
EndIf
EndIf
If place1 = symbol1 and place2 = symbol1 and place3 = symbol1 or place4 = symbol1 and place5 = symbol1 and place6 = symbol1 or place7 = symbol1 and place8 = symbol1 and place9 = symbol1 or place1 = symbol1 and place4 = symbol1 and place7 = symbol1 or place2 = symbol1 and place5 = symbol1 and place8 = symbol1 or place3 = symbol1 and place6 = symbol1 and place9 = symbol1 or place1 = symbol1 and place5 = symbol1 and place9 = symbol1 or place3 = symbol1 and place5 = symbol1 and place7 = symbol1 then
TextWindow.WriteLine("Player 1 (" + symbol1 + ") wins!")
ElseIf place1 = symbol2 and place2 = symbol2 and place3 = symbol2 or place4 = symbol2 and place5 = symbol2 and place6 = symbol2 or place7 = symbol2 and place8 = symbol2 and place9 = symbol2 or place1 = symbol2 and place4 = symbol2 and place7 = symbol2 or place2 = symbol2 and place5 = symbol2 and place8 = symbol2 or place3 = symbol2 and place6 = symbol2 and place9 = symbol2 or place1 = symbol2 and place5 = symbol2 and place8 = symbol2 or place3 = symbol2 and place5 = symbol2 and place7 = symbol2 then
TextWindow.WriteLine("Player 2 (" + symbol2 + ") wins!")
Else
Goto reset
EndIf

ZX Spectrum Basic[edit]

 
 

Batch File[edit]

This is just a game between two human players.

@echo off
setlocal enabledelayedexpansion
:newgame
set a1=1
set a2=2
set a3=3
set a4=4
set a5=5
set a6=6
set a7=7
set a8=8
set a9=9
set ll=X
set /a zz=0
:display1
cls
echo Player: %ll%
echo %a7%_%a8%_%a9%
echo %a4%_%a5%_%a6%
echo %a1%_%a2%_%a3%
set /p myt=Where would you like to go (choose a number from 1-9 and press enter)?
if !a%myt%! equ %myt% (
set a%myt%=%ll%
goto check
)
goto display1
:check
set /a zz=%zz%+1
if %zz% geq 9 goto newgame
if %a7%+%a8%+%a9% equ %ll%+%ll%+%ll% goto win
if %a4%+%a5%+%a6% equ %ll%+%ll%+%ll% goto win
if %a1%+%a2%+%a3% equ %ll%+%ll%+%ll% goto win
if %a7%+%a5%+%a3% equ %ll%+%ll%+%ll% goto win
if %a1%+%a5%+%a9% equ %ll%+%ll%+%ll% goto win
if %a7%+%a4%+%a1% equ %ll%+%ll%+%ll% goto win
if %a8%+%a5%+%a2% equ %ll%+%ll%+%ll% goto win
if %a9%+%a6%+%a3% equ %ll%+%ll%+%ll% goto win
goto %ll%
:X
set ll=O
goto display1
:O
set ll=X
goto display1
:win
echo %ll% wins!
pause
goto newgame
 

Advanced[edit]

This code makes a version of Tic Tac Toe with more features:

@ECHO OFF
:BEGIN
REM Skill level
set sl=
cls
echo Tic Tac Toe (Q to quit)
echo.
echo.
echo Pick your skill level (press a number)
echo.
echo (1) Children under 6
echo (2) Average Mental Case
echo (3) Oversized Ego
CHOICE /c:123q /n > nul
if errorlevel 4 goto end
if errorlevel 3 set sl=3
if errorlevel 3 goto layout
if errorlevel 2 set sl=2
if errorlevel 2 goto layout
set sl=1
 
:LAYOUT
REM Player turn ("x" or "o")
set pt=
REM Game winner ("x" or "o")
set gw=
REM No moves
set nm=
REM Set to one blank space after equal sign (check with cursor end)
set t1=
set t2=
set t3=
set t4=
set t5=
set t6=
set t7=
set t8=
set t9=
 
:UPDATE
cls
echo (S to set skill level) Tic Tac Toe (Q to quit)
echo.
echo You are the X player.
echo Press the number where you want to put an X.
echo.
echo Skill level %sl% 7 8 9
echo 4 5 6
echo 1 2 3
echo.
echo  : :
echo %t1% : %t2% : %t3%
echo ....:...:....
echo %t4% : %t5% : %t6%
echo ....:...:....
echo %t7% : %t8% : %t9%
echo  : :
if "%gw%"=="x" goto winx2
if "%gw%"=="o" goto wino2
if "%nm%"=="0" goto nomoves
 
:PLAYER
set pt=x
REM Layout is for keypad. Change CHOICE to "/c:123456789sq /n > nul"
REM for numbers to start at top left (also change user layout above).
CHOICE /c:789456123sq /n > nul
if errorlevel 11 goto end
if errorlevel 10 goto begin
if errorlevel 9 goto 9
if errorlevel 8 goto 8
if errorlevel 7 goto 7
if errorlevel 6 goto 6
if errorlevel 5 goto 5
if errorlevel 4 goto 4
if errorlevel 3 goto 3
if errorlevel 2 goto 2
goto 1
 
:1
REM Check if "x" or "o" already in square.
if "%t1%"=="x" goto player
if "%t1%"=="o" goto player
set t1=x
goto check
:2
if "%t2%"=="x" goto player
if "%t2%"=="o" goto player
set t2=x
goto check
:3
if "%t3%"=="x" goto player
if "%t3%"=="o" goto player
set t3=x
goto check
:4
if "%t4%"=="x" goto player
if "%t4%"=="o" goto player
set t4=x
goto check
:5
if "%t5%"=="x" goto player
if "%t5%"=="o" goto player
set t5=x
goto check
:6
if "%t6%"=="x" goto player
if "%t6%"=="o" goto player
set t6=x
goto check
:7
if "%t7%"=="x" goto player
if "%t7%"=="o" goto player
set t7=x
goto check
:8
if "%t8%"=="x" goto player
if "%t8%"=="o" goto player
set t8=x
goto check
:9
if "%t9%"=="x" goto player
if "%t9%"=="o" goto player
set t9=x
goto check
 
:COMPUTER
set pt=o
if "%sl%"=="1" goto skill1
REM (win corner to corner)
if "%t1%"=="o" if "%t3%"=="o" if not "%t2%"=="x" if not "%t2%"=="o" goto c2
if "%t1%"=="o" if "%t9%"=="o" if not "%t5%"=="x" if not "%t5%"=="o" goto c5
if "%t1%"=="o" if "%t7%"=="o" if not "%t4%"=="x" if not "%t4%"=="o" goto c4
if "%t3%"=="o" if "%t7%"=="o" if not "%t5%"=="x" if not "%t5%"=="o" goto c5
if "%t3%"=="o" if "%t9%"=="o" if not "%t6%"=="x" if not "%t6%"=="o" goto c6
if "%t9%"=="o" if "%t7%"=="o" if not "%t8%"=="x" if not "%t8%"=="o" goto c8
REM (win outside middle to outside middle)
if "%t2%"=="o" if "%t8%"=="o" if not "%t5%"=="x" if not "%t5%"=="o" goto c5
if "%t4%"=="o" if "%t6%"=="o" if not "%t5%"=="x" if not "%t5%"=="o" goto c5
REM (win all others)
if "%t1%"=="o" if "%t2%"=="o" if not "%t3%"=="x" if not "%t3%"=="o" goto c3
if "%t1%"=="o" if "%t5%"=="o" if not "%t9%"=="x" if not "%t9%"=="o" goto c9
if "%t1%"=="o" if "%t4%"=="o" if not "%t7%"=="x" if not "%t7%"=="o" goto c7
if "%t2%"=="o" if "%t5%"=="o" if not "%t8%"=="x" if not "%t8%"=="o" goto c8
if "%t3%"=="o" if "%t2%"=="o" if not "%t1%"=="x" if not "%t1%"=="o" goto c1
if "%t3%"=="o" if "%t5%"=="o" if not "%t7%"=="x" if not "%t7%"=="o" goto c7
if "%t3%"=="o" if "%t6%"=="o" if not "%t9%"=="x" if not "%t9%"=="o" goto c9
if "%t4%"=="o" if "%t5%"=="o" if not "%t6%"=="x" if not "%t6%"=="o" goto c6
if "%t6%"=="o" if "%t5%"=="o" if not "%t4%"=="x" if not "%t4%"=="o" goto c4
if "%t7%"=="o" if "%t4%"=="o" if not "%t1%"=="x" if not "%t1%"=="o" goto c1
if "%t7%"=="o" if "%t5%"=="o" if not "%t3%"=="x" if not "%t3%"=="o" goto c3
if "%t7%"=="o" if "%t8%"=="o" if not "%t9%"=="x" if not "%t9%"=="o" goto c9
if "%t8%"=="o" if "%t5%"=="o" if not "%t2%"=="x" if not "%t2%"=="o" goto c2
if "%t9%"=="o" if "%t8%"=="o" if not "%t7%"=="x" if not "%t7%"=="o" goto c7
if "%t9%"=="o" if "%t5%"=="o" if not "%t1%"=="x" if not "%t1%"=="o" goto c1
if "%t9%"=="o" if "%t6%"=="o" if not "%t3%"=="x" if not "%t3%"=="o" goto c3
REM (block general attempts) -----------------------------------------------
if "%t1%"=="x" if "%t2%"=="x" if not "%t3%"=="x" if not "%t3%"=="o" goto c3
if "%t1%"=="x" if "%t5%"=="x" if not "%t9%"=="x" if not "%t9%"=="o" goto c9
if "%t1%"=="x" if "%t4%"=="x" if not "%t7%"=="x" if not "%t7%"=="o" goto c7
if "%t2%"=="x" if "%t5%"=="x" if not "%t8%"=="x" if not "%t8%"=="o" goto c8
if "%t3%"=="x" if "%t2%"=="x" if not "%t1%"=="x" if not "%t1%"=="o" goto c1
if "%t3%"=="x" if "%t5%"=="x" if not "%t7%"=="x" if not "%t7%"=="o" goto c7
if "%t3%"=="x" if "%t6%"=="x" if not "%t9%"=="x" if not "%t9%"=="o" goto c9
if "%t4%"=="x" if "%t5%"=="x" if not "%t6%"=="x" if not "%t6%"=="o" goto c6
if "%t6%"=="x" if "%t5%"=="x" if not "%t4%"=="x" if not "%t4%"=="o" goto c4
if "%t7%"=="x" if "%t4%"=="x" if not "%t1%"=="x" if not "%t1%"=="o" goto c1
if "%t7%"=="x" if "%t5%"=="x" if not "%t3%"=="x" if not "%t3%"=="o" goto c3
if "%t7%"=="x" if "%t8%"=="x" if not "%t9%"=="x" if not "%t9%"=="o" goto c9
if "%t8%"=="x" if "%t5%"=="x" if not "%t2%"=="x" if not "%t2%"=="o" goto c2
if "%t9%"=="x" if "%t8%"=="x" if not "%t7%"=="x" if not "%t7%"=="o" goto c7
if "%t9%"=="x" if "%t5%"=="x" if not "%t1%"=="x" if not "%t1%"=="o" goto c1
if "%t9%"=="x" if "%t6%"=="x" if not "%t3%"=="x" if not "%t3%"=="o" goto c3
REM (block obvious corner to corner)
if "%t1%"=="x" if "%t3%"=="x" if not "%t2%"=="x" if not "%t2%"=="o" goto c2
if "%t1%"=="x" if "%t9%"=="x" if not "%t5%"=="x" if not "%t5%"=="o" goto c5
if "%t1%"=="x" if "%t7%"=="x" if not "%t4%"=="x" if not "%t4%"=="o" goto c4
if "%t3%"=="x" if "%t7%"=="x" if not "%t5%"=="x" if not "%t5%"=="o" goto c5
if "%t3%"=="x" if "%t9%"=="x" if not "%t6%"=="x" if not "%t6%"=="o" goto c6
if "%t9%"=="x" if "%t7%"=="x" if not "%t8%"=="x" if not "%t8%"=="o" goto c8
if "%sl%"=="2" goto skill2
REM (block sneaky corner to corner 2-4, 2-6, etc.)
if "%t2%"=="x" if "%t4%"=="x" if not "%t1%"=="x" if not "%t1%"=="o" goto c1
if "%t2%"=="x" if "%t6%"=="x" if not "%t3%"=="x" if not "%t3%"=="o" goto c3
if "%t8%"=="x" if "%t4%"=="x" if not "%t7%"=="x" if not "%t7%"=="o" goto c7
if "%t8%"=="x" if "%t6%"=="x" if not "%t9%"=="x" if not "%t9%"=="o" goto c9
REM (block offset corner trap 1-8, 1-6, etc.)
if "%t1%"=="x" if "%t6%"=="x" if not "%t8%"=="x" if not "%t8%"=="o" goto c8
if "%t1%"=="x" if "%t8%"=="x" if not "%t6%"=="x" if not "%t6%"=="o" goto c6
if "%t3%"=="x" if "%t8%"=="x" if not "%t4%"=="x" if not "%t4%"=="o" goto c4
if "%t3%"=="x" if "%t4%"=="x" if not "%t8%"=="x" if not "%t8%"=="o" goto c8
if "%t9%"=="x" if "%t4%"=="x" if not "%t2%"=="x" if not "%t2%"=="o" goto c2
if "%t9%"=="x" if "%t2%"=="x" if not "%t4%"=="x" if not "%t4%"=="o" goto c4
if "%t7%"=="x" if "%t2%"=="x" if not "%t6%"=="x" if not "%t6%"=="o" goto c6
if "%t7%"=="x" if "%t6%"=="x" if not "%t2%"=="x" if not "%t2%"=="o" goto c2
 
:SKILL2
REM (block outside middle to outside middle)
if "%t2%"=="x" if "%t8%"=="x" if not "%t5%"=="x" if not "%t5%"=="o" goto c5
if "%t4%"=="x" if "%t6%"=="x" if not "%t5%"=="x" if not "%t5%"=="o" goto c5
REM (block 3 corner trap)
if "%t1%"=="x" if "%t9%"=="x" if not "%t2%"=="x" if not "%t2%"=="o" goto c2
if "%t3%"=="x" if "%t7%"=="x" if not "%t2%"=="x" if not "%t2%"=="o" goto c2
if "%t1%"=="x" if "%t9%"=="x" if not "%t4%"=="x" if not "%t4%"=="o" goto c4
if "%t3%"=="x" if "%t7%"=="x" if not "%t4%"=="x" if not "%t4%"=="o" goto c4
if "%t1%"=="x" if "%t9%"=="x" if not "%t6%"=="x" if not "%t6%"=="o" goto c6
if "%t3%"=="x" if "%t7%"=="x" if not "%t6%"=="x" if not "%t6%"=="o" goto c6
if "%t1%"=="x" if "%t9%"=="x" if not "%t8%"=="x" if not "%t8%"=="o" goto c8
if "%t3%"=="x" if "%t7%"=="x" if not "%t8%"=="x" if not "%t8%"=="o" goto c8
:SKILL1
REM (just take a turn)
if not "%t5%"=="x" if not "%t5%"=="o" goto c5
if not "%t1%"=="x" if not "%t1%"=="o" goto c1
if not "%t3%"=="x" if not "%t3%"=="o" goto c3
if not "%t7%"=="x" if not "%t7%"=="o" goto c7
if not "%t9%"=="x" if not "%t9%"=="o" goto c9
if not "%t2%"=="x" if not "%t2%"=="o" goto c2
if not "%t4%"=="x" if not "%t4%"=="o" goto c4
if not "%t6%"=="x" if not "%t6%"=="o" goto c6
if not "%t8%"=="x" if not "%t8%"=="o" goto c8
set nm=0
goto update
 
:C1
set t1=o
goto check
:C2
set t2=o
goto check
:C3
set t3=o
goto check
:C4
set t4=o
goto check
:C5
set t5=o
goto check
:C6
set t6=o
goto check
:C7
set t7=o
goto check
:C8
set t8=o
goto check
:C9
set t9=o
goto check
 
:CHECK
if "%t1%"=="x" if "%t2%"=="x" if "%t3%"=="x" goto winx
if "%t4%"=="x" if "%t5%"=="x" if "%t6%"=="x" goto winx
if "%t7%"=="x" if "%t8%"=="x" if "%t9%"=="x" goto winx
if "%t1%"=="x" if "%t4%"=="x" if "%t7%"=="x" goto winx
if "%t2%"=="x" if "%t5%"=="x" if "%t8%"=="x" goto winx
if "%t3%"=="x" if "%t6%"=="x" if "%t9%"=="x" goto winx
if "%t1%"=="x" if "%t5%"=="x" if "%t9%"=="x" goto winx
if "%t3%"=="x" if "%t5%"=="x" if "%t7%"=="x" goto winx
if "%t1%"=="o" if "%t2%"=="o" if "%t3%"=="o" goto wino
if "%t4%"=="o" if "%t5%"=="o" if "%t6%"=="o" goto wino
if "%t7%"=="o" if "%t8%"=="o" if "%t9%"=="o" goto wino
if "%t1%"=="o" if "%t4%"=="o" if "%t7%"=="o" goto wino
if "%t2%"=="o" if "%t5%"=="o" if "%t8%"=="o" goto wino
if "%t3%"=="o" if "%t6%"=="o" if "%t9%"=="o" goto wino
if "%t1%"=="o" if "%t5%"=="o" if "%t9%"=="o" goto wino
if "%t3%"=="o" if "%t5%"=="o" if "%t7%"=="o" goto wino
if "%pt%"=="x" goto computer
if "%pt%"=="o" goto update
 
:WINX
set gw=x
goto update
:WINX2
echo You win!
echo Play again (Y,N)?
CHOICE /c:ynsq /n > nul
if errorlevel 4 goto end
if errorlevel 3 goto begin
if errorlevel 2 goto end
goto layout
 
:WINO
set gw=o
goto update
:WINO2
echo Sorry, You lose.
echo Play again (Y,N)?
CHOICE /c:ynsq /n > nul
if errorlevel 4 goto end
if errorlevel 3 goto begin
if errorlevel 2 goto end
goto layout
 
:NOMOVES
echo There are no more moves left!
echo Play again (Y,N)?
CHOICE /c:ynsq /n > nul
if errorlevel 4 goto end
if errorlevel 3 goto begin
if errorlevel 2 goto end
goto layout
 
:END
cls
echo Tic Tac Toe
echo.
REM Clear all variables (no spaces after equal sign).
set gw=
set nm=
set sl=
set pt=
set t1=
set t2=
set t3=
set t4=
set t5=
set t6=
set t7=
set t8=
set t9=

Befunge[edit]

Requires an intepreter with working support for numeric input, which unfortunately excludes most online implementations.

Plays reasonably well, but not perfectly, so can be beaten.

v123456789 --- >9 >48*,:55+\-0g,1v
>9>066+0p076+0p^ ^,," |"_v#%3:- <
:,,0537051v>:#,_$#^5#,5#+<>:#v_55+
74 1098709<^+55"---+---+---"0<v520
69 04560123 >:!#v_0\1v>$2-:6%v>803
6 +0g\66++0p^ $_>#% v#9:-1_ 6/5
5 vv5!/*88\%*28 ::g0_^>9/#v_ "I",
,,5v>5++0p82*/3-:*+\:^v,[email protected] >"uoY",
0+5<v0+66_v#!%2:_55v >:^:" win!"\
1-^ g >$>0" :evom ruoY">:#,_$v>p
\*8+ 65_^#!/*88g0** `0\!`9:::<&<^0
v >:!67+0g:!56+0g *+*+0" :evom "
>"yM">:#,_$ :. 1234+++, 789*+ \0^<
"a s't"98:*+>:#,[email protected]>365*+"ward"48*
 
Output:
 1 | 2 | 3
---+---+---
 4 | 5 | 6
---+---+---
 7 | 8 | 9

Your move: 1

 X | 2 | 3
---+---+---
 4 | 5 | 6
---+---+---
 7 | 8 | 9

My move: 5 

 X | 2 | 3
---+---+---
 4 | O | 6
---+---+---
 7 | 8 | 9

Your move: 2

 X | X | 3
---+---+---
 4 | O | 6
---+---+---
 7 | 8 | 9

My move: 3 

 X | X | O
---+---+---
 4 | O | 6
---+---+---
 7 | 8 | 9

Your move:

C[edit]

Opening alternates between human and computer. Computer never loses.

#include <stdio.h>
#include <stdlib.h>
 
int b[3][3]; /* board. 0: blank; -1: computer; 1: human */
 
int check_winner()
{
int i;
for (i = 0; i < 3; i++) {
if (b[i][0] && b[i][1] == b[i][0] && b[i][2] == b[i][0])
return b[i][0];
if (b[0][i] && b[1][i] == b[0][i] && b[2][i] == b[0][i])
return b[0][i];
}
if (!b[1][1]) return 0;
 
if (b[1][1] == b[0][0] && b[2][2] == b[0][0]) return b[0][0];
if (b[1][1] == b[2][0] && b[0][2] == b[1][1]) return b[1][1];
 
return 0;
}
 
void showboard()
{
const char *t = "X O";
int i, j;
for (i = 0; i < 3; i++, putchar('\n'))
for (j = 0; j < 3; j++)
printf("%c ", t[ b[i][j] + 1 ]);
printf("-----\n");
}
 
#define for_ij for (i = 0; i < 3; i++) for (j = 0; j < 3; j++)
int best_i, best_j;
int test_move(int val, int depth)
{
int i, j, score;
int best = -1, changed = 0;
 
if ((score = check_winner())) return (score == val) ? 1 : -1;
 
for_ij {
if (b[i][j]) continue;
 
changed = b[i][j] = val;
score = -test_move(-val, depth + 1);
b[i][j] = 0;
 
if (score <= best) continue;
if (!depth) {
best_i = i;
best_j = j;
}
best = score;
}
 
return changed ? best : 0;
}
 
const char* game(int user)
{
int i, j, k, move, win = 0;
for_ij b[i][j] = 0;
 
printf("Board postions are numbered so:\n1 2 3\n4 5 6\n7 8 9\n");
printf("You have O, I have X.\n\n");
for (k = 0; k < 9; k++, user = !user) {
while(user) {
printf("your move: ");
if (!scanf("%d", &move)) {
scanf("%*s");
continue;
}
if (--move < 0 || move >= 9) continue;
if (b[i = move / 3][j = move % 3]) continue;
 
b[i][j] = 1;
break;
}
if (!user) {
if (!k) { /* randomize if computer opens, less boring */
best_i = rand() % 3;
best_j = rand() % 3;
} else
test_move(-1, 0);
 
b[best_i][best_j] = -1;
printf("My move: %d\n", best_i * 3 + best_j + 1);
}
 
showboard();
if ((win = check_winner()))
return win == 1 ? "You win.\n\n": "I win.\n\n";
}
return "A draw.\n\n";
}
 
int main()
{
int first = 0;
while (1) printf("%s", game(first = !first));
return 0;
}

C#[edit]

This implementation is purposely wordy because Tic-Tac-Toe is often a starting level program.
It tries to show a number of C# code features while still keeping each function small and understandable.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
 
namespace RosettaTicTacToe
{
class Program
{
 
/*================================================================
*Pieces (players and board)
*================================================================*/

static string[][] Players = new string[][] {
new string[] { "COMPUTER", "X" }, // computer player
new string[] { "HUMAN", "O" } // human player
};
 
const int Unplayed = -1;
const int Computer = 0;
const int Human = 1;
 
// GameBoard holds index into Players[] (0 or 1) or Unplayed (-1) if location not yet taken
static int[] GameBoard = new int[9];
 
static int[] corners = new int[] { 0, 2, 6, 8 };
 
static int[][] wins = new int[][] {
new int[] { 0, 1, 2 }, new int[] { 3, 4, 5 }, new int[] { 6, 7, 8 },
new int[] { 0, 3, 6 }, new int[] { 1, 4, 7 }, new int[] { 2, 5, 8 },
new int[] { 0, 4, 8 }, new int[] { 2, 4, 6 } };
 
 
/*================================================================
*Main Game Loop (this is what runs/controls the game)
*================================================================*/

static void Main(string[] args)
{
while (true)
{
Console.Clear();
Console.WriteLine("Welcome to Rosetta Code Tic-Tac-Toe for C#.");
initializeGameBoard();
displayGameBoard();
int currentPlayer = rnd.Next(0, 2); // current player represented by Players[] index of 0 or 1
Console.WriteLine("The first move goes to {0} who is playing {1}s.\n", playerName(currentPlayer), playerToken(currentPlayer));
while (true)
{
int thisMove = getMoveFor(currentPlayer);
if (thisMove == Unplayed)
{
Console.WriteLine("{0}, you've quit the game ... am I that good?", playerName(currentPlayer));
break;
}
playMove(thisMove, currentPlayer);
displayGameBoard();
if (isGameWon())
{
Console.WriteLine("{0} has won the game!", playerName(currentPlayer));
break;
}
else if (isGameTied())
{
Console.WriteLine("Cat game ... we have a tie.");
break;
}
currentPlayer = getNextPlayer(currentPlayer);
}
if (!playAgain())
return;
}
}
 
/*================================================================
*Move Logic
*================================================================*/

static int getMoveFor(int player)
{
if (player == Human)
return getManualMove(player);
else
{
//int selectedMove = getManualMove(player);
//int selectedMove = getRandomMove(player);
int selectedMove = getSemiRandomMove(player);
//int selectedMove = getBestMove(player);
Console.WriteLine("{0} selects position {1}.", playerName(player), selectedMove + 1);
return selectedMove;
}
}
 
static int getManualMove(int player)
{
while (true)
{
Console.Write("{0}, enter you move (number): ", playerName(player));
ConsoleKeyInfo keyInfo = Console.ReadKey();
Console.WriteLine(); // keep the display pretty
if (keyInfo.Key == ConsoleKey.Escape)
return Unplayed;
if (keyInfo.Key >= ConsoleKey.D1 && keyInfo.Key <= ConsoleKey.D9)
{
int move = keyInfo.KeyChar - '1'; // convert to between 0..8, a GameBoard index position.
if (GameBoard[move] == Unplayed)
return move;
else
Console.WriteLine("Spot {0} is already taken, please select again.", move + 1);
}
else
Console.WriteLine("Illegal move, please select again.\n");
}
}
 
static int getRandomMove(int player)
{
int movesLeft = GameBoard.Count(position => position == Unplayed);
int x = rnd.Next(0, movesLeft);
for (int i = 0; i < GameBoard.Length; i++) // walk board ...
{
if (GameBoard[i] == Unplayed && x < 0) // until we reach the unplayed move.
return i;
x--;
}
return Unplayed;
}
 
// plays random if no winning move or needed block.
static int getSemiRandomMove(int player)
{
int posToPlay;
if (checkForWinningMove(player, out posToPlay))
return posToPlay;
if (checkForBlockingMove(player, out posToPlay))
return posToPlay;
return getRandomMove(player);
}
 
// purposely not implemented (this is the thinking part).
static int getBestMove(int player)
{
return -1;
}
 
static bool checkForWinningMove(int player, out int posToPlay)
{
posToPlay = Unplayed;
foreach (var line in wins)
if (twoOfThreeMatchPlayer(player, line, out posToPlay))
return true;
return false;
}
 
static bool checkForBlockingMove(int player, out int posToPlay)
{
posToPlay = Unplayed;
foreach (var line in wins)
if (twoOfThreeMatchPlayer(getNextPlayer(player), line, out posToPlay))
return true;
return false;
}
 
static bool twoOfThreeMatchPlayer(int player, int[] line, out int posToPlay)
{
int cnt = 0;
posToPlay = int.MinValue;
foreach (int pos in line)
{
if (GameBoard[pos] == player)
cnt++;
else if (GameBoard[pos] == Unplayed)
posToPlay = pos;
}
return cnt == 2 && posToPlay >= 0;
}
 
static void playMove(int boardPosition, int player)
{
GameBoard[boardPosition] = player;
}
 
static bool isGameWon()
{
return wins.Any(line => takenBySamePlayer(line[0], line[1], line[2]));
}
 
static bool takenBySamePlayer(int a, int b, int c)
{
return GameBoard[a] != Unplayed && GameBoard[a] == GameBoard[b] && GameBoard[a] == GameBoard[c];
}
 
static bool isGameTied()
{
return !GameBoard.Any(spot => spot == Unplayed);
}
 
/*================================================================
*Misc Methods
*================================================================*/

static Random rnd = new Random();
 
static void initializeGameBoard()
{
for (int i = 0; i < GameBoard.Length; i++)
GameBoard[i] = Unplayed;
}
 
static string playerName(int player)
{
return Players[player][0];
}
 
static string playerToken(int player)
{
return Players[player][1];
}
 
static int getNextPlayer(int player)
{
return (player + 1) % 2;
}
 
static void displayGameBoard()
{
Console.WriteLine(" {0} | {1} | {2}", pieceAt(0), pieceAt(1), pieceAt(2));
Console.WriteLine("---|---|---");
Console.WriteLine(" {0} | {1} | {2}", pieceAt(3), pieceAt(4), pieceAt(5));
Console.WriteLine("---|---|---");
Console.WriteLine(" {0} | {1} | {2}", pieceAt(6), pieceAt(7), pieceAt(8));
Console.WriteLine();
}
 
static string pieceAt(int boardPosition)
{
if (GameBoard[boardPosition] == Unplayed)
return (boardPosition + 1).ToString(); // display 1..9 on board rather than 0..8
return playerToken(GameBoard[boardPosition]);
}
 
private static bool playAgain()
{
Console.WriteLine("\nDo you want to play again?");
return Console.ReadKey(false).Key == ConsoleKey.Y;
}
}
 
}
Output:
Welcome to Rosetta Code Tic-Tac-Toe for C#.
 1 | 2 | 3
---|---|---
 4 | 5 | 6
---|---|---
 7 | 8 | 9

The first move goes to HUMAN who is playing Os.

HUMAN, enter you move (number): 5
 1 | 2 | 3
---|---|---
 4 | O | 6
---|---|---
 7 | 8 | 9

COMPUTER selects position 7.
 1 | 2 | 3
---|---|---
 4 | O | 6
---|---|---
 X | 8 | 9

HUMAN, enter you move (number): 0
Illegal move, please select again.

HUMAN, enter you move (number): 1
 O | 2 | 3
---|---|---
 4 | O | 6
---|---|---
 X | 8 | 9

COMPUTER selects position 9.
 O | 2 | 3
---|---|---
 4 | O | 6
---|---|---
 X | 8 | X

HUMAN, enter you move (number):

C++[edit]

 
#include <windows.h>
#include <iostream>
#include <string>
 
//--------------------------------------------------------------------------------------------------
using namespace std;
 
//--------------------------------------------------------------------------------------------------
enum players { Computer, Human, Draw, None };
const int iWin[8][3] = { { 0, 1, 2 }, { 3, 4, 5 }, { 6, 7, 8 }, { 0, 3, 6 }, { 1, 4, 7 }, { 2, 5, 8 }, { 0, 4, 8 }, { 2, 4, 6 } };
 
//--------------------------------------------------------------------------------------------------
class ttt
{
public:
ttt() { _p = rand() % 2; reset(); }
 
void play()
{
int res = Draw;
while( true )
{
drawGrid();
while( true )
{
if( _p ) getHumanMove();
else getComputerMove();
 
drawGrid();
 
res = checkVictory();
if( res != None ) break;
 
++_p %= 2;
}
 
if( res == Human ) cout << "CONGRATULATIONS HUMAN --- You won!";
else if( res == Computer ) cout << "NOT SO MUCH A SURPRISE --- I won!";
else cout << "It's a draw!";
 
cout << endl << endl;
 
string r;
cout << "Play again( Y / N )? "; cin >> r;
if( r != "Y" && r != "y" ) return;
 
++_p %= 2;
reset();
 
}
}
 
private:
void reset()
{
for( int x = 0; x < 9; x++ )
_field[x] = None;
}
 
void drawGrid()
{
system( "cls" );
 
COORD c = { 0, 2 };
SetConsoleCursorPosition( GetStdHandle( STD_OUTPUT_HANDLE ), c );
 
cout << " 1 | 2 | 3 " << endl;
cout << "---+---+---" << endl;
cout << " 4 | 5 | 6 " << endl;
cout << "---+---+---" << endl;
cout << " 7 | 8 | 9 " << endl << endl << endl;
 
int f = 0;
for( int y = 0; y < 5; y += 2 )
for( int x = 1; x < 11; x += 4 )
{
if( _field[f] != None )
{
COORD c = { x, 2 + y };
SetConsoleCursorPosition( GetStdHandle( STD_OUTPUT_HANDLE ), c );
string o = _field[f] == Computer ? "X" : "O";
cout << o;
}
f++;
}
 
c.Y = 9;
SetConsoleCursorPosition( GetStdHandle( STD_OUTPUT_HANDLE ), c );
}
 
int checkVictory()
{
for( int i = 0; i < 8; i++ )
{
if( _field[iWin[i][0]] != None &&
_field[iWin[i][0]] == _field[iWin[i][1]] && _field[iWin[i][1]] == _field[iWin[i][2]] )
{
return _field[iWin[i][0]];
}
}
 
int i = 0;
for( int f = 0; f < 9; f++ )
{
if( _field[f] != None )
i++;
}
if( i == 9 ) return Draw;
 
return None;
}
 
void getHumanMove()
{
int m;
cout << "Enter your move ( 1 - 9 ) ";
while( true )
{
m = 0;
do
{ cin >> m; }
while( m < 1 && m > 9 );
 
if( _field[m - 1] != None )
cout << "Invalid move. Try again!" << endl;
else break;
}
 
_field[m - 1] = Human;
}
 
void getComputerMove()
{
int move = 0;
 
do{ move = rand() % 9; }
while( _field[move] != None );
 
for( int i = 0; i < 8; i++ )
{
int try1 = iWin[i][0], try2 = iWin[i][1], try3 = iWin[i][2];
 
if( _field[try1] != None && _field[try1] == _field[try2] && _field[try3] == None )
{
move = try3;
if( _field[try1] == Computer ) break;
}
 
if( _field[try1] != None && _field[try1] == _field[try3] && _field[try2] == None )
{
move = try2;
if( _field[try1] == Computer ) break;
}
 
if( _field[try2] != None && _field[try2] == _field[try3] && _field[try1] == None )
{
move = try1;
if( _field[try2] == Computer ) break;
}
}
_field[move] = Computer;
 
}
 
 
int _p;
int _field[9];
};
//--------------------------------------------------------------------------------------------------
int main( int argc, char* argv[] )
{
srand( GetTickCount() );
 
ttt tic;
tic.play();
 
return 0;
}
//--------------------------------------------------------------------------------------------------
 
Output:
Computer plays 'X' and human plays 'O'
 1 | 2 | X
---+---+---
 X | 5 | 6
---+---+---
 7 | O | 9

Enter your move ( 1 - 9 )

Common Lisp[edit]

 
(defun generate-board ()
(loop repeat 9 collect nil))
 
(defparameter *straights* '((1 2 3) (4 5 6) (7 8 9) (1 4 7) (2 5 8) (3 6 9) (1 5 9) (3 5 7)))
(defparameter *current-player* 'x)
 
(defun get-board-elt (n board)
(nth (1- n) board))
 
(defun legal-p (n board)
(null (get-board-elt n board)))
 
(defun set-board-elt (n board symbol)
(if (legal-p n board)
(setf (nth (1- n) board) symbol)
(progn (format t "Illegal move. Try again.~&")
(set-board-elt (read) board symbol))))
 
(defun list-legal-moves (board)
(loop for i from 1 to (length board)
when (legal-p i board)
collect i))
 
(defun get-random-element (lst)
(nth (random (length lst)) lst))
 
(defun multi-non-nil-eq (lst)
(and (notany #'null lst)
(notany #'null (mapcar #'(lambda (x) (eq (car lst) x)) lst))
(car lst)))
 
(defun elements-of-straights (board)
(loop for i in *straights*
collect (loop for j from 0 to 2
collect (get-board-elt (nth j i) board))))
 
(defun find-winner (board)
(car (remove-if #'null (mapcar #'multi-non-nil-eq (elements-of-straights board)))))
 
(defun set-player (mark)
(format t "Shall a computer play as ~a? (y/n)~&" mark)
(let ((response (read)))
(cond ((equalp response 'y) t)
((equalp response 'n) nil)
(t (format t "Come again?~&")
(set-player mark)))))
 
(defun player-move (board symbol)
(format t "~%Player ~a, please input your move.~&" symbol)
(set-board-elt (read) board symbol)
(format t "~%"))
 
(defun computer-move (board symbol)
(let ((move (get-random-element (list-legal-moves board))))
(set-board-elt move board symbol)
(format t "~%computer selects ~a~%~%" move)))
 
(defun computer-move-p (current-player autoplay-x-p autoplay-o-p)
(if (eq current-player 'x)
autoplay-x-p
autoplay-o-p))
 
(defun perform-turn (current-player board autoplay-x-p autoplay-o-p)
(if (computer-move-p current-player autoplay-x-p autoplay-o-p)
(computer-move board current-player)
(player-move board current-player)))
 
(defun switch-player ()
(if (eq *current-player* 'x)
(setf *current-player* 'o)
(setf *current-player* 'x)))
 
(defun display-board (board)
(loop for i downfrom 2 to 0
do (loop for j from 1 to 3
initially (format t "|")
do (format t "~a|" (or (get-board-elt (+ (* 3 i) j) board) (+ (* 3 i) j)))
finally (format t "~&"))))
 
(defun tic-tac-toe ()
(setf *current-player* 'x)
(let ((board (generate-board))
(autoplay-x-p (set-player 'x))
(autoplay-o-p (set-player 'o)))
(format t "~%")
(loop until (or (find-winner board) (null (list-legal-moves board)))
do (display-board board)
do (perform-turn *current-player* board autoplay-x-p autoplay-o-p)
do (switch-player)
finally (if (find-winner board)
(format t "The winner is ~a!" (find-winner board))
(format t "It's a tie.")))))
 
Output:
CL-USER> (tic-tac-toe)
Shall a computer play as X? (y/n)
n
Shall a computer play as O? (y/n)
y

|7|8|9|
|4|5|6|
|1|2|3|

Player X, please input your move.
5

|7|8|9|
|4|X|6|
|1|2|3|

computer selects 8

|7|O|9|
|4|X|6|
|1|2|3|

Player X, please input your move.

D[edit]

import std.stdio, std.string, std.algorithm, std.conv, std.random,
std.ascii, std.array, std.range, std.math;
 
struct GameBoard {
dchar[9] board = "123456789";
enum : dchar { human = 'X', computer = 'O' }
enum Game { going, humanWins, computerWins, draw }
 
const pure nothrow @safe @nogc invariant() {
int nHuman = 0, nComputer = 0;
foreach (immutable i, immutable c; board)
if (c.isDigit)
assert(i == c - '1'); // In correct position?
else {
assert(c == human || c == computer);
(c == human ? nHuman : nComputer)++;
}
assert(abs(nHuman - nComputer) <= 1);
}
 
string toString() const pure {
return format("%(%-(%s|%)\n-+-+-\n%)", board[].chunks(3));
}
 
bool isAvailable(in int i) const pure nothrow @safe @nogc {
return i >= 0 && i < 9 && board[i].isDigit;
}
 
auto availablePositions() const pure nothrow @safe /*@nogc*/ {
return 9.iota.filter!(i => isAvailable(i));
}
 
Game winner() const pure nothrow @safe /*@nogc*/ {
static immutable wins = [[0, 1, 2], [3, 4, 5], [6, 7, 8],
[0, 3, 6], [1, 4, 7], [2, 5, 8],
[0, 4, 8], [2, 4, 6]];
 
foreach (immutable win; wins) {
immutable bw0 = board[win[0]];
if (bw0.isDigit)
continue; // Nobody wins on this one.
 
if (bw0 == board[win[1]] && bw0 == board[win[2]])
return bw0 == GameBoard.human ?
Game.humanWins :
Game.computerWins;
}
 
return availablePositions.empty ? Game.draw: Game.going;
}
 
bool isFinished() const pure nothrow @safe /*@nogc*/ {
return winner != Game.going;
}
 
int computerMove() const // Random move.
out(res) {
assert(res >= 0 && res < 9 && isAvailable(res));
} body {
// return availablePositions.array.choice;
return availablePositions.array[uniform(0, $)];
}
}
 
 
GameBoard playGame() {
GameBoard board;
bool playsHuman = true;
 
while (!board.isFinished) {
board.writeln;
 
int move;
if (playsHuman) {
do {
writef("Your move (available moves: %s)? ",
board.availablePositions.map!q{ a + 1 });
readf("%d\n", &move);
move--; // Zero based indexing.
if (move < 0)
return board;
} while (!board.isAvailable(move));
} else
move = board.computerMove;
 
assert(board.isAvailable(move));
writefln("\n%s chose %d", playsHuman ? "You" : "I", move + 1);
board.board[move] = playsHuman ? GameBoard.human :
GameBoard.computer;
playsHuman = !playsHuman; // Switch player.
}
 
return board;
}
 
 
void main() {
"Tic-tac-toe game player.\n".writeln;
immutable outcome = playGame.winner;
 
final switch (outcome) {
case GameBoard.Game.going:
"Game stopped.".writeln;
break;
case GameBoard.Game.humanWins:
"\nYou win!".writeln;
break;
case GameBoard.Game.computerWins:
"\nI win.".writeln;
break;
case GameBoard.Game.draw:
"\nDraw".writeln;
break;
}
}
Output:
Tic-tac-toe game player.

1|2|3
-+-+-
4|5|6
-+-+-
7|8|9
Your move (available moves: [1, 2, 3, 4, 5, 6, 7, 8, 9])? 1

You chose 1
X|2|3
-+-+-
4|5|6
-+-+-
7|8|9

I chose 2
X|O|3
-+-+-
4|5|6
-+-+-
7|8|9
Your move (available moves: [3, 4, 5, 6, 7, 8, 9])? 5

You chose 5
X|O|3
-+-+-
4|X|6
-+-+-
7|8|9

I chose 3
X|O|O
-+-+-
4|X|6
-+-+-
7|8|9
Your move (available moves: [4, 6, 7, 8, 9])? 9

You chose 9

You win!

EasyLang[edit]

It uses minimax with alpha-beta pruning. Therefore, the computer never loses.

Run it

len f[] 9
state = 0
set_textsize 14
#
func init . .
set_linewidth 2
clear_screen
set_color 666
move_pen 34 4
draw_line 34 80
move_pen 62 4
draw_line 62 80
move_pen 10 28
draw_line 86 28
move_pen 10 56
draw_line 86 56
set_linewidth 2.5
for i range 9
f[i] = 0
.
if state = 1
set_timer 0.2
.
.
func draw ind . .
c = ind mod 3
r = ind div 3
x = c * 28 + 20
y = r * 28 + 14
if f[ind] = 4
set_color 900
move_pen x - 7 y - 7
draw_line x + 7 y + 7
move_pen x + 7 y - 7
draw_line x - 7 y + 7
elif f[ind] = 1
set_color 009
move_pen x y
draw_circle 10
set_color -2
draw_circle 7.5
.
.
func sum3 a d . st .
for i range 3
s += f[a]
a += d
.
if s = 3
st = -1
elif s = 12
st = 1
.
.
func rate . res done .
res = 0
for i range 3
call sum3 i * 3 1 res
.
for i range 3
call sum3 i 3 res
.
call sum3 0 4 res
call sum3 2 2 res
cnt = 1
for i range 9
if f[i] = 0
cnt += 1
.
.
res *= cnt
done = 1
if res = 0 and cnt > 1
done = 0
.
.
func minmax player alpha beta . rval rmov .
call rate rval done
if done = 1
if player = 1
rval = -rval
.
else
rval = alpha
start = random 9
mov = start
repeat
if f[mov] = 0
f[mov] = player
call minmax (5 - player) (-beta) (-rval) val h
val = -val
f[mov] = 0
if val > rval
rval = val
rmov = mov
.
.
mov = (mov + 1) mod 9
until mov = start or rval >= beta
.
.
.
func show_result val . .
set_color 555
move_pen 16 84
if val < 0
# this never happens
draw_text "You won"
elif val > 0
draw_text "You lost"
else
draw_text "Tie"
.
state += 2
.
func computer . .
call minmax 4 -11 11 val mov
f[mov] = 4
call draw mov
call rate val done
state = 0
if done = 1
call show_result val
.
.
func human . .
mov = floor ((mouse_x - 6) / 28) + 3 * floor (mouse_y / 28)
if f[mov] = 0
f[mov] = 1
call draw mov
call rate val done
state = 1
if done = 1
call show_result val
else
set_timer 0.5
.
.
.
on timer
call computer
.
on mouse_down
if state = 0
if mouse_x > 6 and mouse_x < 90 and mouse_y < 84
call human
.
elif state >= 2
state -= 2
call init
.
.
call init

Erlang[edit]

The program will randomly chose if the computer ("X") or the user ("O") starts. The computer look ahead is only one level. Perhaps the computer might lose?

 
-module(tic_tac_toe).
 
-export( [task/0] ).
 
task() -> io:fwrite( "Result: ~p.~n", [turn(player(random:uniform()), board())] ).
 
 
 
board() -> [{X, erlang:integer_to_list(X)} || X <- lists:seq(1, 9)].
 
board_tuples( Selections, Board ) -> [lists:keyfind(X, 1, Board) || X <- Selections].
 
computer_move( Player, Board ) ->
[N | _T] = lists:flatten( [X(Player, Board) || X <- [fun computer_move_win/2, fun computer_move_block/2, fun computer_move_middle/2, fun computer_move_random/2]] ),
N.
 
computer_move_block( Player, Board ) -> computer_move_two_same_player( player(false, Player), Board ).
 
computer_move_middle( _Player, Board ) ->
{5, Y} = lists:keyfind( 5, 1, Board ),
computer_move_middle( is_empty(Y) ).
 
computer_move_middle( true ) -> [5];
computer_move_middle( false ) -> [].
 
computer_move_random( _Player, Board ) ->
Ns = [X || {X, Y} <- Board, is_empty(Y)],
[lists:nth( random:uniform(erlang:length(Ns)), Ns )].
 
computer_move_two_same_player( Player, Board ) ->
Selections = [X || X <- three_in_row_all(), is_two_same_player(Player, X, Board)],
computer_move_two_same_player( Player, Board, Selections ).
 
computer_move_two_same_player( _Player, _Board, [] ) -> [];
computer_move_two_same_player( _Player, Board, [Selection | _T] ) -> [X || {X, Y} <- board_tuples(Selection, Board), is_empty(Y)].
 
computer_move_win( Player, Board ) -> computer_move_two_same_player( Player, Board ).
 
is_empty( Square ) -> Square =< "9". % Do not use < "10".
 
is_finished( Board ) -> is_full( Board ) orelse is_three_in_row( Board ).
 
is_full( Board ) -> [] =:= [X || {X, Y} <- Board, is_empty(Y)].
 
is_three_in_row( Board ) ->
Fun = fun(Selections) -> is_three_in_row_same_player( board_tuples(Selections, Board) ) end,
lists:any( Fun, three_in_row_all() ).
 
is_three_in_row_same_player( Selected ) -> three_in_row_player( Selected ) =/= no_player.
 
is_two_same_player( Player, Selections, Board ) -> is_two_same_player( Player, [{X, Y} || {X, Y} <- board_tuples(Selections, Board), not is_empty(Y)] ).
 
is_two_same_player( Player, [{_X, Player}, {_Y, Player}] ) -> true;
is_two_same_player( _Player, _Selected ) -> false.
 
player( Random ) when Random > 0.5 -> "O";
player( _Random ) -> "X".
 
player( true, _Player ) -> finished;
player( false, "X" ) -> "O";
player( false, "O" ) -> "X".
 
result( Board ) -> result( is_full(Board), Board ).
 
result( true, _Board ) -> draw;
result( false, Board ) ->
[Winners] = [Selections || Selections <- three_in_row_all(), three_in_row_player(board_tuples(Selections, Board)) =/= no_player],
"Winner is " ++ three_in_row_player( board_tuples(Winners, Board) ).
 
three_in_row_all() -> three_in_row_horisontal() ++ three_in_row_vertical() ++ three_in_row_diagonal().
three_in_row_diagonal() -> [[1,5,9], [3,5,7]].
three_in_row_horisontal() -> [[1,2,3], [4,5,6], [7,8,9]].
three_in_row_vertical() -> [[1,4,7], [2,5,8], [3,6,9]].
 
three_in_row_player( [{_X, Player}, {_Y, Player}, {_Z, Player}] ) -> three_in_row_player( not is_empty(Player), Player );
three_in_row_player( _Selected ) -> no_player.
 
three_in_row_player( true, Player ) -> Player;
three_in_row_player( false, _Player ) -> no_player.
 
turn( finished, Board ) -> result( Board );
turn( "X"=Player, Board ) ->
N = computer_move( Player, Board ),
io:fwrite( "Computer, ~p, selected ~p~n", [Player, N] ),
New_board = [{N, Player} | lists:keydelete(N, 1, Board)],
turn( player(is_finished(New_board), Player), New_board );
turn( "O"=Player, Board ) ->
[turn_board_write_horisontal(X, Board) || X <- three_in_row_horisontal()],
Ns = [X || {X, Y} <- Board, is_empty(Y)],
Prompt = lists:flatten( io_lib:format("Player, ~p, select one of ~p: ", [Player, Ns]) ),
N = turn_next_move( Prompt, Ns ),
New_board = [{N, Player} | lists:keydelete(N, 1, Board)],
turn( player(is_finished(New_board), Player), New_board ).
 
turn_board_write_horisontal( Selections, Board ) ->
Tuples = [lists:keyfind(X, 1, Board) || X <- Selections],
[io:fwrite( "~p ", [Y]) || {_X, Y} <- Tuples],
io:fwrite( "~n" ).
 
turn_next_move( Prompt, Ns ) ->
{ok,[N]} = io:fread( Prompt, "~d" ),
turn_next_move_ok( lists:member(N, Ns), Prompt, Ns, N ).
 
turn_next_move_ok( true, _Prompt, _Ns, N ) -> N;
turn_next_move_ok( false, Prompt, Ns, _N ) -> turn_next_move( Prompt, Ns ).
 
Output:
96> tic_tac_toe:task().
"1" "2" "3" 
"4" "5" "6" 
"7" "8" "9" 
Player, "O", select one of [1,2,3,4,5,6,7,8,9]: 5
Computer, "X", selected 2
"1" "X" "3" 
"4" "O" "6" 
"7" "8" "9" 
Player, "O", select one of [1,3,4,6,7,8,9]: 1
Computer, "X", selected 9
"O" "X" "3" 
"4" "O" "6" 
"7" "8" "X" 
Player, "O", select one of [3,4,6,7,8]: 3
Computer, "X", selected 7
"O" "X" "O" 
"4" "O" "6" 
"X" "8" "X" 
Player, "O", select one of [4,6,8]: 8
Computer, "X", selected 6
"O" "X" "O" 
"4" "O" "X" 
"X" "O" "X" 
Player, "O", select one of [4]: 4
Result: draw.

ERRE[edit]

Taken from ERRE distribution disk: comments and messages are in Italian.

!--------------------------------------------
! TRIS.R : gioca a tris contro l'operatore
!--------------------------------------------

PROGRAM TRIS

DIM TRIS%[9],T1%[9],PIECES$[3]

!$SEGMENT=$B800

!$INCLUDE="PC.LIB"

PROCEDURE DELAY(COUNT%)
  FOR Z%=1 TO COUNT DO
  END FOR
END PROCEDURE

PROCEDURE SET_BOARD
!
! Disegna lo schema del gioco
!
  CLS
  BLOAD("TRIS.BLD",0)
!$KEY
END PROCEDURE

PROCEDURE PUT_PIECES
!
! Pone i pezzi sulla scacchiera
!
  Z%=0
  FOR ROW%=6 TO 12 STEP 3 DO     ! posizioni assolute sullo schermo
    FOR COL%=32 TO 48 STEP 8 DO
      LOCATE(ROW%+1,COL%+1)
      Z%=Z%+1
      PRINT(PIECES$[TRIS%[Z%]])
    END FOR
  END FOR
END PROCEDURE

PROCEDURE COMPUTE_MOVE(A%)
  CASE A% OF
    2-> C1%=C1%+1            END ->
    4-> C2%=C2%+1            END ->
    8-> S1%=TRUE  S2%=TRUE   END ->
    3-> N1%=N1%+1            END ->
    9-> N2%=N2%+1            END ->
   27-> S1%=FALSE S2%=FALSE  END ->
 END CASE
END PROCEDURE

PROCEDURE PREPAREMOVE(T1%[],I%->M%)
!
! Prepara la mossa del calcolatore
!
   T1%[I%]=2
   C1%=0
   C2%=0
   N1%=0
   N2%=0
   FOR K%=0 TO 2 DO
     COMPUTE_MOVE(T1%[3*K%+1]*T1%[3*K%+2]*T1%[3*K%+3])
     COMPUTE_MOVE(T1%[K%+1]*T1%[K%+4]*T1%[K%+7])
   END FOR
   COMPUTE_MOVE(T1%[1]*T1%[5]*T1%[9])
   COMPUTE_MOVE(T1%[3]*T1%[5]*T1%[7])
   M%=-63*N2%+31*C2%-15*N1%+7*C1%
END PROCEDURE

PROCEDURE COMPUTER_MOVE
!
! Coordina le mosse del calcolatore
!
  MAXSCORE%=-1000
  FOR I%=1 TO 9 DO
    IF TRIS%[I%]=1
      THEN
       PREPAREMOVE(TRIS%[],I%->MV%)
       EXIT IF S2% AND NOT S1%
       IF S1% AND S2%
         THEN
          TRIS%[I%]=2
          DIARY$=DIARY$+"c"+MID$(STR$(I%),2)+"*"
          PUT_PIECES
          EXIT
       END IF
       IF MV%=0
         THEN
          MOVE%=I%
          EXIT
       END IF
       IF MV%>MAXSCORE%
         THEN
          MOVE%=I%
          MAXSCORE%=MV%
       END IF
    END IF
  END FOR
  IF NOT S2%
    THEN
     TRIS%[MOVE%]=2
     DIARY$=DIARY$+"c"+MID$(STR$(MOVE%),2)+";"
     PUT_PIECES
     NMOVE%=NMOVE%-1
     S1%=(NMOVE%=0)
  END IF
END PROCEDURE

PROCEDURE PLAYER_MOVE
!
! Gioca l'avversario umano usando i tasti cursore per lo spostamento
!
  LOCATE(19,13)
  PRINT("Tocca a te ....                  ")
  REPEAT
    ROW%=7
    COL%=32
    LOCATE(ROW%+1,COL%+1)
    PRINT("Ü")
    REPEAT
      GET(B$)
      IF LEN(B$)=2 THEN
        CASE ASC(RIGHT$(B$,1)+CHR$(0)) OF
          77-> ! codice tastiera per CRSR =>
             LOCATE(ROW%+1,COL%+1)
             PRINT(" ")
             COL%=-(COL%+8)*(COL%<=40)-32*(COL%>40)
             LOCATE(ROW%+1,COL%+1)
             PRINT("Ü")
          END ->
          75-> ! codice tastiera per CRSR <=
             LOCATE(ROW%+1,COL%+1)
             PRINT(" ")
             COL%=-(COL%-8)*(COL%>=40)-48*(COL%<40)
             LOCATE(ROW%+1,COL%+1)
             PRINT("Ü")
          END ->
          80-> ! codice tastiera per CRSR DOWN
             LOCATE(ROW%+1,COL%+1)
             PRINT(" ")
             ROW%=-(ROW%+3)*(ROW%<=10)-7*(ROW%>10)
             LOCATE(ROW%+1,COL%+1)
             PRINT("Ü")
          END ->
          72-> ! codice tastiera per CRSR UP
             LOCATE(ROW%+1,COL%+1)
             PRINT(" ")
             ROW%=-(ROW%-3)*(ROW%>=10)-13*(ROW%<10)
             LOCATE(ROW%+1,COL%+1)
             PRINT("Ü")
          END ->
       END CASE
      END IF
     UNTIL B$=CHR$(13)
     MM%=ROW%+COL%/8-10 ! da coordinate schermo a coordinate scacchiera
   UNTIL TRIS%[MM%]=1
  TRIS%[MM%]=3
  LOCATE(ROW%+1,COL%+1)
  PRINT(" ")
  DIARY$=DIARY$+"p"+MID$(STR$(MM%),2)+";"
  PUT_PIECES
  NMOVE%=NMOVE%-1
  S1%=(NMOVE%=0)
  LOCATE(19,13)
  PRINT(STRING$(45," "))
END PROCEDURE

BEGIN
  DATA(" ","+","o")
  SET_BOARD
  REPEAT
    S1%=FALSE    S2%=FALSE   ! determinano lo stato della partita
    NMOVE%=9
    FOR Z%=1 TO 3 DO
       READ(PIECES$[Z%])
    END FOR
    FOR Z%=1 TO 9 DO
        TRIS%[Z%]=1
    END FOR
    LOCATE(19,13)
    PRINT("Giochi per primo ?")
    REPEAT
      GET(A$)
    UNTIL A$="S" OR A$="s" OR A$="N" OR A$="n"
    PUT_PIECES
    FOR INDICE%=1 TO 9 DO
      IF A$="s" OR A$="S"
        THEN
          PLAYER_MOVE
          EXIT IF S1% OR S2%
          COMPUTER_MOVE
          EXIT IF S1% OR S2%
        ELSE
          COMPUTER_MOVE
          EXIT IF S1% OR S2%
          PLAYER_MOVE
          EXIT IF S1% OR S2%
      END IF
   END FOR
   LOCATE(19,13)
   CASE TRUE OF
     (S1% AND NOT S2%)->
        PRINT("E' finita pari !!!     ")
     END ->
     (S2% AND NOT S1%)->
        PRINT("HAI VINTO !!!          ")
     END ->
     (S1% AND S2%)->
        PRINT("HO VINTO IO !!!        ")
     END ->
   END CASE
   DELAY(500)
   LOCATE(19,13)
   PRINT(DIARY$)
   DELAY(500)
   LOCATE(19,13)
   PRINT("Vuoi giocare ancora ?       ")
   REPEAT
     GET(A$)
   UNTIL A$="S" OR A$="s" OR A$="N" OR A$="n"
 UNTIL A$="N" OR A$="n"
END PROGRAM
Output:

A game example

 ░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░
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 ░░▒▒▓▓                                                                  ▓▓▒▒░░
 ░░▒▒▓▓ ┌───────────────┐   ╔═══════╤═══════╤═══════╗   ┌────────────┐   ▓▓▒▒░░
 ░░▒▒▓▓ │───── TRIS ────│   ║   +   │   o   │   +   ║   │Il calcola- │   ▓▓▒▒░░
 ░░▒▒▓▓ │               │   ║       │       │       ║   │tore non può│   ▓▓▒▒░░
 ░░▒▒▓▓ │Si gioca contro│   ╟───────┼───────┼───────╢   │perdere e   │   ▓▓▒▒░░
 ░░▒▒▓▓ │il calcolatore.│   ║   +   │   o   │   o   ║   │perciò il   │   ▓▓▒▒░░
 ░░▒▒▓▓ │Per muoversi   │   ║       │       │       ║   │giocatore   │   ▓▓▒▒░░
 ░░▒▒▓▓ │usare i tasti  │   ╟───────┼───────┼───────╢   │può al mas- │   ▓▓▒▒░░
 ░░▒▒▓▓ │cursore e ◄──┘ │   ║   o   │   +   │   o   ║   │simo pareg- │   ▓▓▒▒░░
 ░░▒▒▓▓ │per confermare.│   ║       │       │       ║   │giare.      │   ▓▓▒▒░░
 ░░▒▒▓▓ └───────────────┘   ╚═══════╧═══════╧═══════╝   └────────────┘   ▓▓▒▒░░
 ░░▒▒▓▓                                                                  ▓▓▒▒░░
 ░░▒▒▓▓                                                                  ▓▓▒▒░░
 ░░▒▒▓▓  ┌────────────────────────────────────────────────────────────┐  ▓▓▒▒░░
 ░░▒▒▓▓  │  Vuoi giocare ancora ?                                     │  ▓▓▒▒░░
 ░░▒▒▓▓  └────────────────────────────────────────────────────────────┘  ▓▓▒▒░░
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Euphoria[edit]

Works with: OpenEuphoria

No computer AI

 
include std/console.e
include std/text.e
include std/search.e
include std/sequence.e
 
sequence board
sequence players = {"X","O"}
 
function DisplayBoard()
for i = 1 to 3 do
for j = 1 to 3 do
printf(1,"%s",board[i][j])
if j < 3 then
printf(1,"%s","|")
end if
end for
if i < 3 then
puts(1,"\n-----\n")
else
puts(1,"\n\n")
end if
end for
 
return 1
end function
 
function CheckWinner()
sequence temp = board
for a = 1 to 2 do
for i = 1 to 3 do
if equal({"X","X","X"},temp[i]) then
puts(1,"X wins\n\n")
return 1
elsif equal({"O","O","O"},temp[i]) then
puts(1,"O wins\n\n")
return 1
end if
end for
temp = columnize(board)
end for
if equal({"X","X","X"},{board[1][1],board[2][2],board[3][3]}) or
equal({"X","X","X"},{board[1][3],board[2][2],board[3][1]}) then
puts(1,"X wins\n")
return 1
elsif equal({"O","O","O"},{board[1][1],board[2][2],board[3][3]}) or
equal({"O","O","O"},{board[1][3],board[2][2],board[3][1]}) then
puts(1,"O wins\n")
return 1
end if
 
if moves = 9 then
puts(1,"Draw\n\n")
return 1
end if
 
return 0
end function
 
integer turn, row, column, moves
sequence replay
while 1 do
board = repeat(repeat(" ",3),3)
DisplayBoard()
turn = rand(2)
moves = 0
 
while 1 do
while 1 do
printf(1,"%s's turn\n",players[turn])
row = prompt_number("Enter row: ",{})
column = prompt_number("Enter column: ",{})
if match(board[row][column]," ") then
board[row][column] = players[turn]
moves += 1
exit
else
puts(1,"Space already taken - pick again\n")
end if
end while
 
DisplayBoard()
 
if CheckWinner() then
exit
end if
 
if turn = 1 then
turn = 2
else
turn = 1
end if
end while
 
replay = lower(prompt_string("Play again (y/n)?\n\n"))
 
if match(replay,"n") then
exit
end if
 
end while
 
Output:
 | |
-----
 | |
-----
 | |

O's turn
Enter row: 1
Enter column: 1
O| |
-----
 | |
-----
 | |

X's turn
Enter row: 3
Enter column: 3
O| |
-----
 | |
-----
 | |X

O's turn
Enter row: 3
Enter column: 1
O| |
-----
 | |
-----
O| |X

X's turn
Enter row: 2
Enter column: 1
O| |
-----
X| |
-----
O| |X

O's turn
Enter row: 2
Enter column: 2
O| |
-----
X|O|
-----
O| |X

X's turn
Enter row: 1
Enter column: 3
O| |X
-----
X|O|
-----
O| |X

O's turn
Enter row: 1
Enter column: 2
O|O|X
-----
X|O|
-----
O| |X

X's turn
Enter row: 3
Enter column: 2
O|O|X
-----
X|O|
-----
O|X|X

O's turn
Enter row: 2
Enter column: 3
O|O|X
-----
X|O|O
-----
O|X|X

Draw

Play again (y/n)?

F#[edit]

A purely-functional solution with a naive (but perfect) computer player implementation. The first move is played randomly by the computer.

type Brick =
| Empty
| Computer
| User
 
let brickToString = function
| Empty -> ' '
| Computer -> 'X'
| User -> 'O'
 
// y -> x -> Brick
type Board = Map<int, Map<int, Brick> >
 
let emptyBoard =
let emptyRow = Map.ofList [0,Empty; 1,Empty; 2,Empty]
Map.ofList [0,emptyRow; 1,emptyRow; 2,emptyRow]
 
let get (b:Board) (x,y) = b.[y].[x]
 
let set player (b:Board) (x,y) : Board =
let row = b.[y].Add(x, player)
b.Add(y, row)
 
let winningPositions =
[for x in [0..2] -> x,x] // first diagonal
 ::[for x in [0..2] -> 2-x,x] // second diagonal
 ::[for y in [0..2] do
yield! [[for x in [0..2]->(y,x)]; // columns
[for x in [0..2] -> (x,y)]]] // rows
 
let hasWon player board =
List.exists
(fun ps -> List.forall (fun pos -> get board pos = player) ps)
winningPositions
 
let freeSpace board =
[for x in 0..2 do
for y in 0..2 do
if get board (x,y) = Empty then yield x,y]
 
type Evaluation =
| Win
| Draw
| Lose
 
let rec evaluate board move =
let b2 = set Computer board move
if hasWon Computer b2 then Win
else
match freeSpace b2 with
| [] -> Draw
| userChoices ->
let b3s = List.map (set User b2) userChoices
if List.exists (hasWon User) b3s then Lose
elif List.exists (fun b3 -> bestOutcome b3 = Lose) b3s
then Lose
elif List.exists (fun b3 -> bestOutcome b3 = Draw) b3s
then Draw
else Win
 
and findBestChoice b =
match freeSpace b with
| [] -> ((-1,-1), Draw)
| choices ->
match List.tryFind (fun c -> evaluate b c = Win) choices with
| Some c -> (c, Win)
| None -> match List.tryFind (fun c -> evaluate b c = Draw) choices with
| Some c -> (c, Draw)
| None -> (List.head choices, Lose)
 
and bestOutcome b = snd (findBestChoice b)
 
let bestChoice b = fst (findBestChoice b)
 
let computerPlay b = set Computer b (bestChoice b)
 
let printBoard b =
printfn " | A | B | C |"
printfn "---+---+---+---+"
for y in 0..2 do
printfn " %d | %c | %c | %c |"
(3-y)
(get b (0,y) |> brickToString)
(get b (1,y) |> brickToString)
(get b (2,y) |> brickToString)
printfn "---+---+---+---+"
 
let rec userPlay b =
printfn "Which field do you play? (format: a1)"
let input = System.Console.ReadLine()
if input.Length <> 2
|| input.[0] < 'a' || input.[0] > 'c'
|| input.[1] < '1' || input.[1] > '3' then
printfn "illegal input"
userPlay b
else
let x = int(input.[0]) - int('a')
let y = 2 - int(input.[1]) + int('1')
if get b (x,y) <> Empty then
printfn "Field is not free."
userPlay b
else
set User b (x,y)
 
let rec gameLoop b player =
if freeSpace b = [] then
printfn "Game over. Draw."
elif player = Computer then
printfn "Computer plays..."
let b2 = computerPlay b
printBoard b2
if hasWon Computer b2 then
printfn "Game over. I have won."
else
gameLoop b2 User
elif player = User then
let b2 = userPlay b
printBoard b2
if hasWon User b2 then
printfn "Game over. You have won."
else
gameLoop b2 Computer
 
// randomly choose an element of a list
let choose =
let rnd = new System.Random()
fun (xs:_ list) -> xs.[rnd.Next(xs.Length)]
 
// play first brick randomly
printfn "Computer starts."
let b = set Computer emptyBoard (choose (freeSpace emptyBoard))
printBoard b
gameLoop b User

Example game:

Computer starts.
   | A | B | C |
---+---+---+---+
 3 |   |   | X |
---+---+---+---+
 2 |   |   |   |
---+---+---+---+
 1 |   |   |   |
---+---+---+---+
Which field do you play? (format: a1)
a1
   | A | B | C |
---+---+---+---+
 3 |   |   | X |
---+---+---+---+
 2 |   |   |   |
---+---+---+---+
 1 | O |   |   |
---+---+---+---+
Computer plays...
   | A | B | C |
---+---+---+---+
 3 | X |   | X |
---+---+---+---+
 2 |   |   |   |
---+---+---+---+
 1 | O |   |   |
---+---+---+---+
Which field do you play? (format: a1)
b3
   | A | B | C |
---+---+---+---+
 3 | X | O | X |
---+---+---+---+
 2 |   |   |   |
---+---+---+---+
 1 | O |   |   |
---+---+---+---+
Computer plays...
   | A | B | C |
---+---+---+---+
 3 | X | O | X |
---+---+---+---+
 2 |   |   |   |
---+---+---+---+
 1 | O |   | X |
---+---+---+---+
Which field do you play? (format: a1)
c2
   | A | B | C |
---+---+---+---+
 3 | X | O | X |
---+---+---+---+
 2 |   |   | O |
---+---+---+---+
 1 | O |   | X |
---+---+---+---+
Computer plays...
   | A | B | C |
---+---+---+---+
 3 | X | O | X |
---+---+---+---+
 2 |   | X | O |
---+---+---+---+
 1 | O |   | X |
---+---+---+---+
Game over. I have won.

Fortran[edit]

Objective: write program in less than 100 lines, not using semicolons. Computer never loses, but plays as random as possible. Player gets first move of first game. Afterwards, first move alternates between computer and player.

 
! This is a fortran95 implementation of the game of tic-tac-toe.
! - Objective was to use less than 100 lines.
! - No attention has been devoted to efficiency.
! - Indentation by findent: https://sourceforge.net/projects/findent/
! - This is free software, use as you like at own risk.
! - Compile: gfortran -o tictactoe tictactoe.f90
! - Run: ./tictactoe
! Comments to: wvermin at gmail dot com
module tic
implicit none
integer :: b(9)
contains
logical function iswin(p)
integer,intent(in) :: p
iswin = &
all(b([1,2,3])==p).or.all(b([4,5,6])==p).or.all(b([7,8,9])==p).or.&
all(b([1,4,7])==p).or.all(b([2,5,8])==p).or.all(b([3,6,9])==p).or.&
all(b([1,5,9])==p).or.all(b([3,5,7])==p)
end function iswin
subroutine printb(mes)
character(len=*) :: mes
integer :: i,j
character :: s(0:2) = ['.','X','O']
print "(3a3,' ',3i3)",(s(b(3*i+1:3*i+3)),(j,j=3*i+1,3*i+3),i=0,2)
if(mes /= ' ') print "(/,a)",mes
end subroutine printb
integer recursive function minmax(player,bestm) result(bestv)
integer :: player,bestm,move,v,bm,win=1000,inf=100000
real :: x
if (all(b .ne. 0)) then
bestv = 0
else
bestv = -inf
do move=1,9
if (b(move) == 0) then
b(move) = player
if (iswin(player)) then
v = win
else
call random_number(x)
v = -minmax(3-player,bm) - int(10*x)
endif
if (v > bestv) then
bestv = v
bestm = move
endif
b(move) = 0
if (v == win) exit
endif
enddo
endif
end function minmax
end module tic
program tictactoe
! computer: player=1, user: player=2
use tic
implicit none
integer :: move,ios,v,bestmove,ply,player=2,k,values(8)
integer,allocatable :: seed(:)
call date_and_time(values=values)
call random_seed(size=k)
allocate(seed(k))
seed = values(8)+1000*values(7)+60*1000*values(6)+60*60*1000*values(5)
call random_seed(put=seed)
mainloop: do
b = 0
call printb('You have O, I have X. You enter 0: game ends.')
plyloop: do ply=0,4
if (player == 2 .or. ply >0 ) then ! user move
write(*,"(/,a)",advance='no'),'Your move? (0..9) '
getloop: do
readloop: do
read (*,*,iostat=ios),move
if (ios == 0 .and. move >= 0 .and. move <= 9) exit readloop
write(*,"(a)",advance='no'),'huh? Try again (0..9): '
enddo readloop
if ( move == 0) exit mainloop
if (b(move) == 0) exit getloop
write(*,"(a)",advance='no'),'Already occupied, again (0..9): '
enddo getloop
b(move) = 2
if(iswin(2)) then ! this should not happen
call printb('***** You win *****')
exit plyloop
endif
endif
v = minmax(1,bestmove) ! computer move
b(bestmove) = 1
if(iswin(1)) then
call printb('***** I win *****')
exit plyloop
endif
write(*,"(/,a,i3)"), 'My move: ',bestmove
call printb(' ')
enddo plyloop
if(ply == 5) write(*,"('***** Draw *****',/)")
player = 3-player
enddo mainloop
end program
 

FreeBASIC[edit]

graphics mode[edit]

 
 
'About 400 lines of code, but it is a graphical (GUI ish) i.e. mouse driven.
'I have made provision for the player to beat the computer now and then.
 
 
Type box
As long x,y
As long wide,high,index
Dim As ulong colour
As String caption
Declare Sub show
Declare Sub NewCaption(s As String)
Declare Constructor
Declare Constructor(x As long,y As long,wide As long,_
high As long,index As long,colour As ulong,caption As String)
End Type
Constructor box
End Constructor
Constructor box(x As long,y As long,wide As long,_
high As long,index As long,colour As ulong,caption As String)
this.x=x
this.y=y
this.wide=wide
this.high=high
this.index=index
this.colour=colour
this.caption=caption
End Constructor
'ALL PROCEDURES:
Declare Function inside(B As box,px As long,py As long) As long
Declare Sub make_frame_image(im As ulong Pointer)
Declare Sub setup_grid(boxes() As box,cellsacross As long,cellsdown As long,xp As long,yp As long,w As long,h As long)
Declare Function all_clicked(b() As box) As long
Declare Sub OnCLICK(a() As box,b As box)
Declare Sub refresh_screen(b() As box,f1 As long=0,f2 As long=0)
Declare Function Get_Mouse_Events(boxes() As box) As long
Declare Sub thickline(x1 As long,y1 As long,x2 As long,y2 As long,thickness As Single,colour As ulong,im As Any Pointer=0)
Declare Sub lineto(x1 As long,y1 As long,x2 As long,y2 As long,l As long,th As Single,col As ulong,im As Any Pointer=0)
Declare Sub thickcircle(x As long,y As long,rad As long,th As Single,col As ulong,im As Any Pointer=0)
Declare Sub startup(b() As box)
Declare Sub get_computer_events(b() As box)
 
Declare Sub finish
'Macro used by more than one procedure
#macro incircle(cx,cy,radius,x,y)
(cx-x)*(cx-x) +(cy-y)*(cy-y)<= radius*radius
#endmacro
'=============== RUN ============================
Screen 19,32',1,16
Color ,Rgb(233,236,216) 'background colour
windowtitle string(100," ")+"Noughts and crosses"
'Globals:
Dim Shared As ulong Pointer frame
Dim Shared As long computer,player
Dim Shared As String msg1,msg2,message
message="In Play"
msg1="Computer Start"
msg2="Player Start"
'Custom Frame
frame=Imagecreate(800,600)
 
Dim As box boxes(0 To 9)
 
setup_grid(boxes(),3,3,175,85,150,150)
make_frame_image(frame)
 
Do
If player=0 And computer=0 Then
startup(boxes())
End If
 
If player Then
Get_Mouse_Events(boxes())
End If
 
If computer Then
get_computer_events(boxes())
End If
 
If all_clicked(boxes()) Then get_computer_events(boxes())
Loop Until Inkey=Chr(27)
finish
 
Sub box.show
Line(this.x,this.y)-(this.x+this.wide,this.y+this.high),this.colour,bf
Line(this.x,this.y)-(this.x+this.wide,this.y+this.high),Rgb(200,200,200),b
''Draw String(this.x+.5*this.wide-4*Len(this.caption),this.y+(.5*this.high-4)),this.caption,Rgb(0,0,0)
If this.index=0 Then
Draw String(this.x+.5*this.wide-4*Len(this.caption),this.y+.5*this.high-6),this.caption,Rgb(0,0,0)
End If
End Sub
Sub box.NewCaption(s As String)
Var cx=(this.x+this.x+this.wide)/2
Var cy=(this.y+this.y+this.high)/2
If s="X" Then
For k As long=20 To 0 Step -1
lineto(cx,cy,this.x,this.y,50,k,Rgb(50+10*k,5*k,0),frame)
lineto(cx,cy,this.x+this.wide,this.y+this.high,50,k,Rgb(50+10*k,5*k,0),frame)
lineto(cx,cy,this.x,this.y+this.high,50,k,Rgb(50+10*k,5*k,0),frame)
lineto(cx,cy,this.x+this.wide,this.y,50,k,Rgb(50+10*k,5*k,0),frame)
Next k
Else
For k As long=20 To 0 Step -1
thickcircle(cx,cy,40,k,Rgb(50+10*k,5*k,0),frame)
Next k
End If
End Sub
Sub get_computer_events(b() As box)
#define other(n) b(n).caption<>"0" And b(n).caption<>"C"
#define another(n) b(n).caption="0"
#define rr(f,l) (Rnd*((l)-(f))+(f))
Dim As long flag,i,k,Cwin,Pwin,NoWin
Static As long firstclick
var chance="001100"
dim as long ch
'horiz player finish
For x As long=1 To 3
If b(1+k).caption="0" And b(2+k).caption="0" And another((3+k)) Then b(3+k).Caption="0":Pwin=1:Goto fin
If b(2+k).caption="0" And b(3+k).caption="0" And another((1+k))Then b(1+k).Caption="0":Pwin=1=1:Goto fin
If b(1+k).caption="0" And b(3+k).caption="0" And another((2+k))Then b(2+k).Caption="0":Pwin=1:Goto fin
k=k+3
Next x
k=0
'vert player finish
For x As long=1 To 3
If b(1+k).caption="0" And b(4+k).caption="0" And another((7+k)) Then b(7+k).Caption="0":Pwin=1:Goto fin
If b(4+k).caption="0" And b(7+k).caption="0" And another((1+k))Then b(1+k).Caption="0":Pwin=1:Goto fin
If b(1+k).caption="0" And b(7+k).caption="0" And another((4+k))Then b(4+k).Caption="0":Pwin=1:Goto fin
k=k+1
Next x
k=0
'player finish main diag
If b(1+k).caption="0" And b(5+k).caption="0" And another((9+k)) Then b(9+k).Caption="0":Pwin=1:Goto fin
If b(1+k).caption="0" And b(9+k).caption="0" And another((5+k))Then b(5+k).Caption="0":Pwin=1:Goto fin
If b(5+k).caption="0" And b(9+k).caption="0" And another((1+k))Then b(1+k).Caption="0":Pwin=1:Goto fin
'player finish other diag
If b(7+k).caption="0" And b(5+k).caption="0" And another((3+k)) Then b(3+k).Caption="0":Pwin=1:Goto fin
If b(5+k).caption="0" And b(3+k).caption="0" And another((7+k))Then b(7+k).Caption="0":Pwin=1:Goto fin
If b(7+k).caption="0" And b(3+k).caption="0" And another((5+k))Then b(5+k).Caption="0":Pwin=1:Goto fin
 
'horiz computer finish
For x As long=1 To 3
If b(1+k).caption="C" And b(2+k).caption="C" And other((3+k)) Then b(3+k).Caption="C":Cwin=1:Goto fin
If b(2+k).caption="C" And b(3+k).caption="C" And other((1+k))Then b(1+k).Caption="C":Cwin=1:Goto fin
If b(1+k).caption="C" And b(3+k).caption="C" And other((2+k))Then b(2+k).Caption="C":Cwin=1:Goto fin
k=k+3
Next x
k=0
'vert computer finish
For x As long=1 To 3
If b(1+k).caption="C" And b(4+k).caption="C" And other((7+k)) Then b(7+k).Caption="C":Cwin=1:Goto fin
If b(4+k).caption="C" And b(7+k).caption="C" And other((1+k))Then b(1+k).Caption="C":Cwin=1:Goto fin
If b(1+k).caption="C" And b(7+k).caption="C" And other((4+k))Then b(4+k).Caption="C":Cwin=1:Goto fin
k=k+1
Next x
k=0
'computer finish main diag
If b(1+k).caption="C" And b(5+k).caption="C" And other((9+k)) Then b(9+k).Caption="C":Cwin=1:Goto fin
If b(1+k).caption="C" And b(9+k).caption="C" And other((5+k))Then b(5+k).Caption="C":Cwin=1:Goto fin
If b(5+k).caption="C" And b(9+k).caption="C" And other((1+k))Then b(1+k).Caption="C":Cwin=1:Goto fin
'computer finish other diag
If b(7+k).caption="C" And b(5+k).caption="C" And other((3+k)) Then b(3+k).Caption="C":Cwin=1:Goto fin
If b(5+k).caption="C" And b(3+k).caption="C" And other((7+k))Then b(7+k).Caption="C":Cwin=1:Goto fin
If b(7+k).caption="C" And b(3+k).caption="C" And other((5+k))Then b(5+k).Caption="C":Cwin=1:Goto fin
 
'block horizontals
For x As long=1 To 3
If b(1+k).caption="0" And b(2+k).caption="0" And other((3+k)) Then b(3+k).Caption="C":flag=1:Goto fin
If b(2+k).caption="0" And b(3+k).caption="0" And other((1+k))Then b(1+k).Caption="C":flag=1:Goto fin
If b(1+k).caption="0" And b(3+k).caption="0" And other((2+k))Then b(2+k).Caption="C":flag=1:Goto fin
k=k+3
Next x
k=0
'block verticals
For x As long=1 To 3
If b(1+k).caption="0" And b(4+k).caption="0" And other((7+k)) Then b(7+k).Caption="C":flag=1:Goto fin
If b(4+k).caption="0" And b(7+k).caption="0" And other((1+k))Then b(1+k).Caption="C":flag=1:Goto fin
If b(1+k).caption="0" And b(7+k).caption="0" And other((4+k))Then b(4+k).Caption="C":flag=1:Goto fin
k=k+1
Next x
k=0
'block main diag
If b(1+k).caption="0" And b(5+k).caption="0" And other((9+k)) Then b(9+k).Caption="C":flag=1:Goto fin
If b(1+k).caption="0" And b(9+k).caption="0" And other((5+k))Then b(5+k).Caption="C":flag=1:Goto fin
If b(5+k).caption="0" And b(9+k).caption="0" And other((1+k))Then b(1+k).Caption="C":flag=1:Goto fin
'block other diag
If b(7+k).caption="0" And b(5+k).caption="0" And other((3+k)) Then b(3+k).Caption="C":flag=1:Goto fin
If b(5+k).caption="0" And b(3+k).caption="0" And other((7+k))Then b(7+k).Caption="C":flag=1:Goto fin
If b(7+k).caption="0" And b(3+k).caption="0" And other((5+k))Then b(5+k).Caption="C":flag=1:Goto fin
 
If firstclick=0 Then
firstclick=1
var st="1379"
dim as long i=rr(0,3)
If Valint(b(5).caption)=0 and b(5).caption <> "C" Then b(st[i]-48).caption="C":Goto fin
 
End If
 
ch=rr(0,5)
if chance[ch]-48=1 then
If Valint(b(5).caption)<>0 Then b(5).caption="C":Goto fin
end if
If all_clicked(b()) Then Nowin=1:Goto fin
If flag=0 Then
Randomize
Do
i=rr(1,9)
If Valint(b(i).caption) <> 0 Then b(i).caption="C":Exit Do
Loop
End If
fin:
If Cwin=1 Or Pwin=1 Or NoWin=1 Then
Dim As long mx,my,mb
dim as integer x,y
screencontrol 0,x,y
for z as single=0 to 8*atn(1) step .001
dim as integer xx=x+100*cos(z)
dim as integer yy=y+100*sin(z)
screencontrol 100,xx,yy
next z
screencontrol 100,x,y
If Cwin=1 Then Message="You Loose"
If Pwin=1 Then Message="You WIN"
If Nowin=1 Then Message="DRAW"
 
cwin=0:k=0:pWin=0:Nowin=0:firstclick=0'i
Do
Getmouse mx,my,,mb
If inside(b(0),mx,my) And mb=1 Then finish
 
Var ic=incircle(500,55,20,mx,my)
If incircle(500,55,20,mx,my) And mb=1 Then Exit Do
refresh_screen(b(),ic)
Loop Until Inkey=chr(27)
For z As long=1 To Ubound(b)
b(z).caption=Str(b(z).index)
Next z
Imagedestroy frame
frame=Imagecreate(800,600)
make_frame_image(frame)
computer=0:player=0
Exit Sub
End If
player=1:computer=0
End Sub
 
Sub startup(b() As box)
message="In Play"
Dim As long mx,my,mb
Getmouse mx,my,,mb
 
For n As long=0 To Ubound(b)
If inside(b(n),mx,my) And mb=1 Then
If b(n).index=0 Then
finish
End If
End If
b(0).colour=Rgb(200,0,0)
Next n
Dim As long f1,f2
If incircle(80,230,10,mx,my) Then
f1=1:f2=0
If mb=1 Then computer=1:player=0
End If
If incircle(670,230,10,mx,my) Then
f1=0:f2=1
If mb=1 Then player=1:computer=0
End If
refresh_screen(b(),f1,f2)
End Sub
Sub thickcircle(x As long,y As long,rad As long,th As Single,col As ulong,im As Any Pointer=0)
Circle(x,y),rad+th/2,col
Circle(x,y),rad-th/2,col
Paint(x,y+rad),col,col
End Sub
 
Sub thickline(x1 As long,_
y1 As long,_
x2 As long,_
y2 As long,_
thickness As Single,_
colour As ulong,_
im As Any Pointer=0)
Dim p As ulong=Rgb(255, 255, 255)
If thickness<2 Then
Line(x1,y1)-(x2,y2),colour
Else
Dim As Double s,h,c
h=Sqr((x2-x1)^2+(y2-y1)^2)
If h=0 Then h=1e-6
s=(y1-y2)/h
c=(x2-x1)/h
For x As long=1 To 2
Line im,(x1+s*thickness/2,y1+c*thickness/2)-(x2+s*thickness/2,y2+c*thickness/2),p
Line im,(x1-s*thickness/2,y1-c*thickness/2)-(x2-s*thickness/2,y2-c*thickness/2),p
Line im,(x1+s*thickness/2,y1+c*thickness/2)-(x1-s*thickness/2,y1-c*thickness/2),p
Line im,(x2+s*thickness/2,y2+c*thickness/2)-(x2-s*thickness/2,y2-c*thickness/2),p
Paint im,((x1+x2)/2, (y1+y2)/2), p, p
p=colour
Next x
End If
End Sub
Sub lineto(x1 As long,y1 As long,x2 As long,y2 As long,l As long,th As Single,col As ulong,im As Any Pointer=0)
Dim As long diffx=x2-x1,diffy=y2-y1,ln=Sqr(diffx*diffx+diffy*diffy)
Dim As Single nx=diffx/ln,ny=diffy/ln
thickline(x1,y1,(x1+l*nx),(y1+l*ny),th,col,im)
End Sub
 
 
Function inside(B As box,px As long,py As long) As long
Return (px>B.x)*(px<(B.x+B.wide))*(py>B.y)*(py<(B.y+B.high))
End Function
Sub make_frame_image(im As ulong Pointer)
#macro map(a,b,x,d,c)
((d)-(c))*((x)-(a))/((b)-(a))+(c)
#endmacro
#macro logo(sx,sy,rad)
For k As Single=-rad/10 To rad/10 Step .5:Circle im,(sx,sy),rad+k,Rgb(15,118,155):Next
For k As Single=-rad/10 To rad/10 Step .5:Circle im,(sx+1.3*rad,sy+rad),rad+k,Rgb(230,193,78),2.,1.7:Next
For k As Single=-rad/10 To rad/10 Step .5:Circle im,(sx+2*1.3*rad,sy),rad+k,Rgb(21,3,0),3.25,3.05:Next
For k As Single=-rad/10 To rad/10 Step .5:Circle im,(sx+3*1.3*rad,sy+rad),rad+k,Rgb(26,143,76),2,1.8:Next
For k As Single=-rad/10 To rad/10 Step .5:Circle im,(sx+4*1.3*rad,sy),rad+k,Rgb(200,63,87),3.25,3.05:Next
#endmacro
For k As long=0 To 50
Var r=map(0,50,k,233,193-20)
Var g=map(0,50,k,236,153-20)
Var b=map(0,50,k,216,19-19)
Line im,(0+k,20+k)-(800-k,600-k),Rgb(r,g,b),b
Next k
For k As long=0 To 20
Var r=map(0,20,k,250,0)
Var g=map(0,20,k,250,0)
Var b=map(0,20,k,250,255)
Line im,(0,k)-(780,k),Rgb(r,g,b)',bf
Next k
logo(60,8,5)
logo(380,8,5)
logo(720,8,5)
End Sub
Sub setup_grid(boxes() As box,cellsacross As long,cellsdown As long,xp As long,yp As long,w As long,h As long)
Dim As long index
For y As long=yp To yp+h*(cellsdown-1) Step h
For x As long=xp To xp+w*(cellsacross-1) Step w
index=index+1
boxes(index)=Type<box>(x,y,w,h,index,Rgb(133,136,116),Str(index))
Next x
Next y
boxes(0)=Type<box>(780,-2,20,24,0,Rgb(200,0,0),"X")
End Sub
 
Function all_clicked(b() As box) As long
Dim As long sum
For z As long=1 To Ubound(b)
sum=sum+Valint(b(z).caption)
Next z
If sum<=0 Then Return -1
End Function
 
Sub OnCLICK(a() As box,b As box)
If b.caption="0" Then Exit Sub
If b.caption="C" Then Exit Sub
If b.caption <> "C" Then b.caption="0"
If b.index=0 Then finish
player=0:computer=1
End Sub
 
Sub refresh_screen(b() As box,f1 As long=0,f2 As long=0)
Screenlock:Cls
For n As long=0 To Ubound(b)
b(n).show 'draw boxes
If b(n).caption="0" Then b(n).NewCaption("X")
If b(n).caption="C" Then b(n).NewCaption("O")
Next n
Put(0,0),frame,trans
Draw String (390,50),message,Rgb(0,0,0)
If message <>"In Play" Then
Circle(500,55),20,Rgb(255,20,255),,,,f
If f1=-1 Then Circle(500,55),20,Rgb(202,200,200),,,,f
Draw String(480,50),"Click",Rgb(0,0,0)
End If
If computer=0 And player=0 Then
Draw String (60,200),msg1,Rgb(0,0,0)
Circle(80,230),10,Rgb(0,0,0)
Circle(80,230),5,Rgb(100,100,100),,,,f
If f1=1 Then Circle(80,230),10,Rgb(200,0,0),,,,f
Draw String (650,200),msg2,Rgb(0,0,0)
Circle(670,230),10,Rgb(0,0,0)
Circle(670,230),5,Rgb(100,100,100),,,,f
If f2=1 Then Circle(670,230),10,Rgb(200,0,0),,,,f
End If
Screenunlock:Sleep 1,1
End Sub
 
Function Get_Mouse_Events(boxes() As box) As long
Static released As long
Static pressed As long
Dim As long mousex,mousey,mousebutton ,x,y
Getmouse mousex,mousey,,mousebutton
Dim As box bar=Type<box>(0,0,780,50,0,0,"")
 
refresh_screen(boxes())
For n As long=0 To Ubound(boxes)
If inside(boxes(n),mousex,mousey) Then
If released Then
boxes(n).colour=Rgb(120,123,103)
If n=0 Then boxes(0).colour=Rgb(255,0,0)
End If
If mousebutton=1 Then
If released Then OnCLICK(boxes(),boxes(n))
Exit For
End If
Else
boxes(n).colour=Rgb(133,136,116)
If n=0 Then boxes(0).colour=Rgb(200,0,0)
End If
Next n
If mousebutton=0 Then released=1 Else released=0 'clean clicks
Return 0
End Function
Sub finish
Screenunlock
Imagedestroy frame
End
End Sub
 


text mode[edit]

 
Screenres 320,240,32
 
'global variables globales
Dim Shared As Integer b(3,3) 'tablero
Dim Shared As Integer mx, my, btns, ox, oy
 
'prueba para ganar posición
'3 victorias horizontales
Function TestWin(t As Integer) As Integer
Dim As Integer win = 0
 
If b(0,0)= t And b(1,0)= t And b(2,0)= t Then win = t
If b(0,1)= t And b(1,1)= t And b(2,1)= t Then win = t
If b(0,2)= t And b(1,2)= t And b(2,2)= t Then win = t
 
'3 en vertical gana
If b(0,0)= t And b(0,1)= t And b(0,2)= t Then win = t
If b(1,0)= t And b(1,1)= t And b(1,2)= t Then win = t
If b(2,0)= t And b(2,1)= t And b(2,2)= t Then win = t
 
'cruzada gana
If b(0,0)= t And b(1,1)= t And b(2,2)= t Then win = t
If b(2,0)= t And b(1,1)= t And b(0,2)= t Then win = t
 
Return win
End Function
 
Sub InicializarTablero()
For j As Integer = 0 To 2
For i As Integer = 0 To 2
b(i,j)=0
Next i
Next j
End Sub
 
Sub DibujaTablero()
Locate 1,1 : Print "+---+---+---+"
For j As Integer = 0 To 2
Print "|";
For i As Integer = 0 To 2
If b(i,j) = 0 Then Print " |";
If b(i,j) = 1 Then Print " x |";
If b(i,j) = 2 Then Print " o |";
Next i
Print !"\n+---+---+---+"
Next j
End Sub
 
Function MovimientoHumano() As Integer
DibujaTablero()
 
Print !"\n HAZ CLICK CON EL MOUSE"
Print "EN LA CASILLA QUE ELIJAS"
Dim As Integer opcion = -1
 
While opcion = -1
Getmouse mx,my,,btns
While btns <> 1 'esperar a pulsar botón
Getmouse mx,my,,btns
Wend
 
mx = (mx-4)\32
my = (my-4)\16
If mx >= 0 And mx < 3 And my >= 0 And my < 3 Then
If b(mx,my) = 0 Then opcion = mx+my*3 'Casilla vacía?
End If
While btns=1
Getmouse mx,my,,btns
Wend
Wend
 
Return opcion
End Function
 
Function MovimientoAleatorio() As Integer
Dim As Integer opcion, i, j
opcion = Int(Rnd(1)*9)
j = Int(opcion/3)
i = opcion - Int(opcion/3)*3
 
While b(i,j) <> 0 Or (opcion > 8 Or opcion < 0)
opcion = Int(Rnd(1)*9)
j = Int(opcion/3)
i = opcion - Int(opcion/3)*3
Wend
 
Return j*3+i
End Function
 
Function MovimientoInteligente(t As Integer) As Integer
Dim As Integer i, j, opcion, t2
opcion = -1 'opcion aún no seleccionada
 
'obtener la ficha t2 de los oponentes
If t = 1 Then t2 = 2 Else t2 = 1
 
'prueba para la casilla central
If b(1,1) = 0 Then opcion = 4
 
'prueba para ganar
If opcion = -1 Then
If b(0,0)= 0 And b(1,0)= t And b(2,0)= t Then opcion = 0
If b(0,0)= t And b(1,0)= 0 And b(2,0)= t Then opcion = 1
If b(0,0)= t And b(1,0)= t And b(2,0)= 0 Then opcion = 2
If b(0,1)= 0 And b(1,1)= t And b(2,1)= t Then opcion = 3
If b(0,1)= t And b(1,1)= 0 And b(2,1)= t Then opcion = 4
If b(0,1)= t And b(1,1)= t And b(2,1)= 0 Then opcion = 5
If b(0,2)= 0 And b(1,2)= t And b(2,2)= t Then opcion = 6
If b(0,2)= t And b(1,2)= 0 And b(2,2)= t Then opcion = 7
If b(0,2)= t And b(1,2)= t And b(2,2)= 0 Then opcion = 8
 
'3 bloques verticales
If b(0,0)= 0 And b(0,1)= t And b(0,2)= t Then opcion = 0
If b(0,0)= t And b(0,1)= 0 And b(0,2)= t Then opcion = 3
If b(0,0)= t And b(0,1)= t And b(0,2)= 0 Then opcion = 6
If b(1,0)= 0 And b(1,1)= t And b(1,2)= t Then opcion = 1
If b(1,0)= t And b(1,1)= 0 And b(1,2)= t Then opcion = 4
If b(1,0)= t And b(1,1)= t And b(1,2)= 0 Then opcion = 7
If b(2,0)= 0 And b(2,1)= t And b(2,2)= t Then opcion = 2
If b(2,0)= t And b(2,1)= 0 And b(2,2)= t Then opcion = 5
If b(2,0)= t And b(2,1)= t And b(2,2)= 0 Then opcion = 8
 
'bloques cruzados
If b(0,0)= 0 And b(1,1)= t And b(2,2)= t Then opcion = 0
If b(0,0)= t And b(1,1)= 0 And b(2,2)= t Then opcion = 4
If b(0,0)= t And b(1,1)= t And b(2,2)= 0 Then opcion = 8
If b(2,0)= 0 And b(1,1)= t And b(0,2)= t Then opcion = 2
If b(2,0)= t And b(1,1)= 0 And b(0,2)= t Then opcion = 4
If b(2,0)= t And b(1,1)= t And b(0,2)= 0 Then opcion = 6
End If
 
'prueba para bloques
If opcion = -1 Then
If b(0,0)= 0 And b(1,0)= t2 And b(2,0)= t2 Then opcion = 0
If b(0,0)= t2 And b(1,0)= 0 And b(2,0)= t2 Then opcion = 1
If b(0,0)= t2 And b(1,0)= t2 And b(2,0)= 0 Then opcion = 2
If b(0,1)= 0 And b(1,1)= t2 And b(2,1)= t2 Then opcion = 3
If b(0,1)= t2 And b(1,1)= 0 And b(2,1)= t2 Then opcion = 4
If b(0,1)= t2 And b(1,1)= t2 And b(2,1)= 0 Then opcion = 5
If b(0,2)= 0 And b(1,2)= t2 And b(2,2)= t2 Then opcion = 6
If b(0,2)= t2 And b(1,2)= 0 And b(2,2)= t2 Then opcion = 7
If b(0,2)= t2 And b(1,2)= t2 And b(2,2)= 0 Then opcion = 8
 
'3 bloques verticales
If b(0,0)= 0 And b(0,1)= t2 And b(0,2)= t2 Then opcion = 0
If b(0,0)= t2 And b(0,1)= 0 And b(0,2)= t2 Then opcion = 3
If b(0,0)= t2 And b(0,1)= t2 And b(0,2)= 0 Then opcion = 6
If b(1,0)= 0 And b(1,1)= t2 And b(1,2)= t2 Then opcion = 1
If b(1,0)= t2 And b(1,1)= 0 And b(1,2)= t2 Then opcion = 4
If b(1,0)= t2 And b(1,1)= t2 And b(1,2)= 0 Then opcion = 7
If b(2,0)= 0 And b(2,1)= t2 And b(2,2)= t2 Then opcion = 2
If b(2,0)= t2 And b(2,1)= 0 And b(2,2)= t2 Then opcion = 5
If b(2,0)= t2 And b(2,1)= t2 And b(2,2)= 0 Then opcion = 8
 
'bloques cruzados
If b(0,0)= 0 And b(1,1)= t2 And b(2,2)= t2 Then opcion = 0
If b(0,0)= t2 And b(1,1)= 0 And b(2,2)= t2 Then opcion = 4
If b(0,0)= t2 And b(1,1)= t2 And b(2,2)= 0 Then opcion = 8
If b(2,0)= 0 And b(1,1)= t2 And b(0,2)= t2 Then opcion = 2
If b(2,0)= t2 And b(1,1)= 0 And b(0,2)= t2 Then opcion = 4
If b(2,0)= t2 And b(1,1)= t2 And b(0,2)= 0 Then opcion = 6
End If
 
If opcion = -1 Then
If b(0,0) = 0 Then opcion = 0
If b(2,0) = 0 Then opcion = 2
If b(0,2) = 0 Then opcion = 6
If b(2,2) = 0 Then opcion = 8
End If
 
'no hay opción de hacer una elección al azar
If opcion = -1 Then
opcion = Int(Rnd(1)*9)
j = Int(opcion/3)
i = opcion - Int(opcion/3)*3
 
'encontrar una casilla vacía
While b(i,j) <> 0
opcion = Int(Rnd(1)*9)
j = Int(opcion/3)
i = opcion - Int(opcion/3)*3
Wend
End If
 
Return opcion
End Function
 
 
InicializarTablero()
DibujaTablero()
Dim As Integer resultado
Dim As Integer jugador = 1
Dim As Integer ContarMovimientos = 0
Dim As Integer ContarPartidas = 0
Dim As Integer movimiento = 0
Dim As Integer i, j
 
Do
'alternar jugadores
If jugador = 1 Then jugador = 2 Else jugador = 1
 
'selecciona tipo de movimiento para cada jugador
If jugador = 1 Then
movimiento = MovimientoHumano()
Else
movimiento = MovimientoInteligente(2)
End If
 
'print "movimiento ="; movimiento
'print "jugador ="; jugador
 
'convertir la elección a las coordenadas del tablero i,j
j = Int(movimiento/3)
i = movimiento - (j*3)
b(i,j) = jugador 'ingrese la ficha de jugador 1 o 2
 
resultado = TestWin(jugador) 'comprobar si el jugador ha ganado
 
DibujaTablero()
ContarMovimientos += 1
 
'=======================================================
'Comprobar final de partida y/o un resultado de victoria
'=======================================================
If ContarMovimientos = 9 Or resultado <> 0 Then
DibujaTablero()
If resultado = 0 Then Print !"\n EMPATE "
If resultado = 1 Then Print !"\n x GANA "
If resultado = 2 Then Print !"\n o GANA "
Print Space(28)
Print "PULSA BARRA ESPACIADORA PARA"
Print "OTRA PARTIDA, ESC PARA SALIR"
Sleep
Cls
 
InicializarTablero() 'reiniciar tablero
ContarMovimientos = 0
ContarPartidas += 1
End If
Loop Until Multikey(&H01)
End
 


Go[edit]

Intermediate, like Python's "Better skilled player." Computer wins and blocks where it can, but otherwise plays randomly. Plays multiple games and keeps score. Player gets first move of first game. Afterwards, loser gets to go first, or after cat games, first move alternates.

package main
 
import (
"bufio"
"fmt"
"math/rand"
"os"
"strings"
)
 
var b []byte
 
func printBoard() {
fmt.Printf("%s\n%s\n%s\n", b[0:3], b[3:6], b[6:9])
}
 
var pScore, cScore int
var pMark, cMark byte = 'X', 'O'
var in = bufio.NewReader(os.Stdin)
 
func main() {
b = make([]byte, 9)
fmt.Println("Play by entering a digit.")
for {
// start of game
for i := range b {
b[i] = '1' + byte(i)
}
computerStart := cMark == 'X'
if computerStart {
fmt.Println("I go first, playing X's")
} else {
fmt.Println("You go first, playing X's")
}
TakeTurns:
for {
if !computerStart {
if !playerTurn() {
return
}
if gameOver() {
break TakeTurns
}
 
}
computerStart = false
computerTurn()
if gameOver() {
break TakeTurns
}
}
fmt.Println("Score: you", pScore, "me", cScore)
fmt.Println("\nLet's play again.")
}
}
 
func playerTurn() bool {
var pm string
var err error
for i := 0; i < 3; i++ { // retry loop
printBoard()
fmt.Printf("%c's move? ", pMark)
if pm, err = in.ReadString('\n'); err != nil {
fmt.Println(err)
return false
}
pm = strings.TrimSpace(pm)
if pm >= "1" && pm <= "9" && b[pm[0]-'1'] == pm[0] {
x := pm[0] - '1'
b[x] = pMark
return true
}
}
fmt.Println("You're not playing right.")
return false
}
 
var choices = make([]int, 9)
 
func computerTurn() {
printBoard()
var x int
defer func() {
fmt.Println("My move:", x+1)
b[x] = cMark
}()
// look for two in a row
block := -1
for _, l := range lines {
var mine, yours int
x = -1
for _, sq := range l {
switch b[sq] {
case cMark:
mine++
case pMark:
yours++
default:
x = sq
}
}
if mine == 2 && x >= 0 {
return // strategy 1: make winning move
}
if yours == 2 && x >= 0 {
block = x
}
}
if block >= 0 {
x = block // strategy 2: make blocking move
return
}
// default strategy: random move
choices = choices[:0]
for i, sq := range b {
if sq == '1'+byte(i) {
choices = append(choices, i)
}
}
x = choices[rand.Intn(len(choices))]
}
 
func gameOver() bool {
// check for win
for _, l := range lines {
if b[l[0]] == b[l[1]] && b[l[1]] == b[l[2]] {
printBoard()
if b[l[0]] == cMark {
fmt.Println("I win!")
cScore++
pMark, cMark = 'X', 'O'
} else {
fmt.Println("You win!")
pScore++
pMark, cMark = 'O', 'X'
}
return true
}
}
// check for empty squares
for i, sq := range b {
if sq == '1'+byte(i) {
return false
}
}
fmt.Println("Cat game.")
pMark, cMark = cMark, pMark
return true
}
 
var lines = [][]int{
{0, 1, 2}, // rows
{3, 4, 5},
{6, 7, 8},
{0, 3, 6}, // columns
{1, 4, 7},
{2, 5, 8},
{0, 4, 8}, // diagonals
{2, 4, 6},
}

Groovy[edit]

Simplified version of Tic Tac Toe for player vs. player (no AI computer-controlled option).

class Main {
 
def input = new Scanner(System.in)
 
static main(args) {
Main main = new Main();
main.play();
}
 
public void play() {
 
TicTackToe game = new TicTackToe();
game.init()
def gameOver = false
def player = game.player1
 
println "Players take turns marking a square. Only squares \n"+
"not already marked can be picked. Once a player has \n"+
"marked three squares in a row, column or diagonal, they win! If all squares \n"+
"are marked and no three squares are the same, a tied game is declared.\n"+
"Player 1 is O and Player 2 is X \n"+
"Have Fun! \n\n"
println "${game.drawBoard()}"
 
while (!gameOver && game.plays < 9) {
 
player = game.currentPlayer == 1 ? game.player1 :game.player2
def validPick = false;
while (!validPick) {
 
def square
println "Next $player, enter move by selecting square's number :"
try {
square = input.nextLine();
} catch (Exception ex) { }
 
if (square.length() == 1 && Character.isDigit(square.toCharArray()[0])) { validPick = game.placeMarker(square) }
if (!validPick) { println "Select another Square" }
 
}
 
(game.checkWinner(player))? gameOver = true : game.switchPlayers()
println(game.drawBoard());
 
}
println "Game Over, " + ((gameOver == true)? "$player Wins" : "Draw")
}
 
}
 
public class TicTackToe {
 
def board = new Object[3][3]
def final player1 = "player 1"
def final player2 = "player 2"
def final marker1 = 'X'
def final marker2 = 'O'
 
int currentPlayer
int plays
 
public TicTacToe(){
 
}
 
 
def init() {
int counter = 0;
(0..2).each { row ->
(0..2).each { col ->
board[row][col] = (++counter).toString();
}
}
plays = 0
currentPlayer =1
}
 
def switchPlayers() {
currentPlayer = (currentPlayer == 1) ? 2:1
plays++
}
 
def placeMarker(play) {
def result = false
(0..2).each { row ->
(0..2).each { col ->
if (board[row][col].toString()==play.toString()){
board[row][col] = (currentPlayer == 1) ? marker2 : marker1;
result = true;
}
}
}
return result;
}
 
def checkWinner(player) {
char current = (player == player1)? marker2: marker1
//Checking
return checkRows(current) || checkColumns(current) ||checkDiagonals(current);
}
 
def checkRows(char current){
(0..2).any{ line ->
board[line].every { it == current}
}
}
 
 
def checkColumns(char current){
(0..2).any{i ->
(0..2).every{j ->
board[j][i]==current }
}
}
 
def checkDiagonals(char current){
def rightDiag = [board[0][0],board[1][1],board[2][2]]
def leftDiag = [board[0][2],board[1][1],board[2][0]]
return rightDiag.every{it == current} || leftDiag.every{it == current}
}
 
 
def drawBoard() {
StringBuilder builder = new StringBuilder("Game board: \n");
(0..2).each { row->
(0..2).each {col ->
builder.append("[" + board[row][col] + "]");
}
builder.append("\n");
}
builder.append("\n");
return builder.toString();
}
}

Haskell[edit]

Computer player has three strategies: 1. Try to block the opponent first, 2. Try to guess a good position for the next move, 3. Place a piece randomly. There are lots of comments throughout the code.

 
module Main where
 
import System.Random
import Data.List (intercalate, find, minimumBy)
import System.Environment (getArgs)
import Data.Char (digitToInt)
import Data.Maybe (listToMaybe, mapMaybe)
import Control.Monad (guard)
import Data.Ord (comparing)
 
-- check if there is a horizontal, vertical or diagonal line of
-- X or O
tictactoe :: String -> Bool
tictactoe a = tictactoeFor 'X' a /= tictactoeFor 'O' a
 
-- check if there is a horizontal, vertical or diagonal line
-- for the given player "n"
tictactoeFor :: Char -> String -> Bool
tictactoeFor n [a,b,c,d,e,f,g,h,i] =
[n,n,n] `elem` [[a,b,c],[d,e,f],[g,h,i],[a,d,g],
[b,e,h],[c,f,i],[a,e,i],[c,e,g]]
 
-- empty game board
start :: String
start = " "
 
-- check if there is an X or an O at the given position
isPossible :: Int -> String -> Bool
isPossible n game = (game !! n) `notElem` "XO"
 
-- try to place an X or an O at a given position.
-- "Right" + modified board means success, "Left" + unmodified board
-- means failure
place :: Int -> Char -> String -> Either String String
place i c game =
if isPossible i game
then Right $ take i game ++ [c] ++ drop (i + 1) game
else Left game
 
-- COMPUTER AI
-- get the number of movements, starting from a given non-empty board
-- and a position for the next movement, until the specified player
-- wins or no movement is possible
-- the positions are chosen sequentially, so there's not much
-- intelligence here anyway
developGame :: Bool -> Int -> Int -> Char -> String -> (Int, Char, String)
developGame iterateMore moves i player game
| i > 8 =
-- if i arrives to the last position, iterate again from 0
-- but do it only once
if iterateMore
then developGame False moves 0 player game
-- draw game (after one iteration, still no winning moves)
else (moves, player, game)
-- draw game (game board full) or a win for the player
| moves == 9 || tictactoeFor player game = (moves, player, game)
-- make a move, if possible, and continue playing
| otherwise = case place i otherPlayer game of
-- position i is not empty. try with the next position
Left _ -> developGame iterateMore moves (i + 1)
otherPlayer game
-- position i was empty, so it was a valid move.
-- change the player and make a new move, starting at pos 0
Right newGame -> developGame iterateMore (moves + 1) 0
otherPlayer newGame
where
otherPlayer = changePlayer player
 
-- COMPUTER AI
-- starting from a given non-empty board, try to guess which position
-- could lead the player to the fastest victory.
bestMoveFor :: Char -> String -> Int
bestMoveFor player game = bestMove
where
-- drive the game to its end for each starting position
continuations = [ (x, developGame True 0 x player game) |
x <- [0..8] ]
-- compare the number of moves of the game and take the
-- shortest one
move (_, (m, _, _)) = m
(bestMove, _) = minimumBy (comparing move) continuations
 
-- canBlock checks if the opponent has two pieces in a row and the
-- other cell in the row is empty, and places the player's piece there,
-- blocking the opponent
canBlock :: Char -> String -> Maybe Int
canBlock p [a,b,c,d,e,f,g,h,i] =
listToMaybe $ mapMaybe blockable [[a,b,c],[d,e,f],[g,h,i],[a,d,g],
[b,e,h],[c,f,i],[a,e,i],[c,e,g]]
where
blockable xs = do
guard $ length (filter (== otherPlayer) xs) == 2
x <- find (`elem` "123456789") xs
return $ digitToInt x
otherPlayer = changePlayer p
 
-- format a game board for on-screen printing
showGame :: String -> String
showGame [a,b,c,d,e,f,g,h,i] =
topBottom ++
"| | 1 | 2 | 3 |\n" ++
topBottom ++
row "0" [[a],[b],[c]] ++
row "3" [[d],[e],[f]] ++
row "6" [[g],[h],[i]]
where
topBottom = "+----+---+---+---+\n"
row n x = "| " ++ n ++ "+ | " ++
intercalate " | " x ++ " |\n" ++ topBottom
 
-- ask the user to press a numeric key and convert it to an int
enterNumber :: IO Int
enterNumber = do
c <- getChar
if c `elem` "123456789"
then do
putStrLn ""
return $ digitToInt c
else do
putStrLn "\nPlease enter a digit!"
enterNumber
 
-- a human player's turn: get the number of pieces put on the board,
-- the next piece to be put (X or O) and a game board, and return
-- a new game state, checking if the piece can be placed on the board.
-- if it can't, make the user try again.
turn :: (Int, Char, String) -> IO (Int, Char, String)
turn (count, player, game) = do
putStr $ "Please tell me where you want to put an " ++
[player] ++ ": "
pos <- enterNumber
case place (pos - 1) player game of
Left oldGame -> do
putStrLn "That place is already taken!\n"
turn (count, player, oldGame)
Right newGame ->
return (count + 1, changePlayer player, newGame)
 
-- alternate between X and O players
changePlayer :: Char -> Char
changePlayer 'O' = 'X'
changePlayer 'X' = 'O'
 
-- COMPUTER AI
-- make an automatic turn, placing an X or an O game board.
-- the first movement is always random.
-- first, the computer looks for two pieces of his opponent in a row
-- and tries to block.
-- otherwise, it tries to guess the best position for the next movement.
-- as a last resort, it places a piece randomly.
autoTurn :: Bool -> (Int, Char, String) -> IO (Int, Char, String)
autoTurn forceRandom (count, player, game) = do
-- try a random position 'cause everything else failed
-- count == 0 overrides the value of forceRandom
i <- if count == 0 || forceRandom
then randomRIO (0,8)
else return $
case canBlock player game of
-- opponent can't be blocked. try to guess
-- the best movement
Nothing -> bestMoveFor player game
-- opponent can be blocked, so just do it!
Just blockPos -> blockPos
-- if trying to place a piece at a calculated position doesn't work,
-- just try again with a random value
case place i player game of
Left oldGame -> autoTurn True (count, player, oldGame)
Right newGame -> do
putStrLn $ "It's player " ++ [player] ++ "'s turn."
return (count + 1, changePlayer player, newGame)
 
-- play a game until someone wins or the board becomes full.
-- depending on the value of the variable "auto", ask the user(s) to
-- put some pieces on the board or do it automatically
play :: Int -> (Int, Char, String) -> IO ()
play auto cpg@(_, player, game) = do
newcpg@(newCount, newPlayer, newGame) <- case auto of
-- if both players are human, always ask them
0 -> turn cpg
-- if both players are computer, always play auto
1 -> autoTurn False cpg
-- X is computer, O is human
2 -> if player == 'X' then autoTurn False cpg else turn cpg
-- X is human, O is computer
3 -> if player == 'O' then autoTurn False cpg else turn cpg
putStrLn $ "\n" ++ showGame newGame
if tictactoe newGame
then putStrLn $ "Player " ++ [changePlayer newPlayer] ++ " wins!\n"
else
if newCount == 9
then putStrLn "Draw!\n"
else play auto newcpg
 
-- main program: greet the user, ask for a game type, ask for the
-- player that'll start the game, and play the game beginning with an
-- empty board
main :: IO ()
main = do
a <- getArgs
if null a
then usage
else do
let option = head a
if option `elem` ["0","1","2","3"]
then do
putStrLn $ "\n" ++ showGame start
let m = read option :: Int
play m (0, 'X', start)
else usage
 
usage :: IO ()
usage = do
putStrLn "TIC-TAC-TOE GAME\n================\n"
putStrLn "How do you want to play?"
putStrLn "Run the program with one of the following options."
putStrLn "0 : both players are human"
putStrLn "1 : both players are computer"
putStrLn "2 : player X is computer and player O is human"
putStrLn "3 : player X is human and player O is computer"
putStrLn "Player X always begins."
 
Output:

Player X is computer, O is human.

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ |   |   |   |
+----+---+---+---+
| 3+ |   |   |   |
+----+---+---+---+
| 6+ |   |   |   |
+----+---+---+---+

It's player X's turn.

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ |   |   |   |
+----+---+---+---+
| 3+ |   | X |   |
+----+---+---+---+
| 6+ |   |   |   |
+----+---+---+---+

Please tell me where you want to put an O: 1

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ | O |   |   |
+----+---+---+---+
| 3+ |   | X |   |
+----+---+---+---+
| 6+ |   |   |   |
+----+---+---+---+

It's player X's turn.

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ | O |   | X |
+----+---+---+---+
| 3+ |   | X |   |
+----+---+---+---+
| 6+ |   |   |   |
+----+---+---+---+

Please tell me where you want to put an O: 7

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ | O |   | X |
+----+---+---+---+
| 3+ |   | X |   |
+----+---+---+---+
| 6+ | O |   |   |
+----+---+---+---+

It's player X's turn.

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ | O |   | X |
+----+---+---+---+
| 3+ | X | X |   |
+----+---+---+---+
| 6+ | O |   |   |
+----+---+---+---+

Please tell me where you want to put an O: 6

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ | O |   | X |
+----+---+---+---+
| 3+ | X | X | O |
+----+---+---+---+
| 6+ | O |   |   |
+----+---+---+---+

It's player X's turn.

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ | O |   | X |
+----+---+---+---+
| 3+ | X | X | O |
+----+---+---+---+
| 6+ | O | X |   |
+----+---+---+---+

Please tell me where you want to put an O: 2

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ | O | O | X |
+----+---+---+---+
| 3+ | X | X | O |
+----+---+---+---+
| 6+ | O | X |   |
+----+---+---+---+

It's player X's turn.

+----+---+---+---+
|    | 1 | 2 | 3 |
+----+---+---+---+
| 0+ | O | O | X |
+----+---+---+---+
| 3+ | X | X | O |
+----+---+---+---+
| 6+ | O | X | X |
+----+---+---+---+

Draw!

Icon and Unicon[edit]

The following works in both Icon and Unicon. The computer plays randomly against a human player, with legal moves enforced and wins/draws notified.

 
# Play TicTacToe
 
$define E " " # empty square
$define X "X" # X piece
$define O "O" # O piece
 
# -- define a board
record Board(a, b, c, d, e, f, g, h, i)
 
procedure display_board (board, player)
write ("\n===============")
write (board.a || " | " || board.b || " | " || board.c)
write ("---------")
write (board.d || " | " || board.e || " | " || board.f)
write ("---------")
write (board.g || " | " || board.h || " | " || board.i)
end
 
# return a set of valid moves (empty positions) in given board
procedure empty_fields (board)
fields := set()
every i := !fieldnames(board) do
if (board[i] == E) then insert (fields, i)
return fields
end
 
procedure game_start ()
return Board (E, E, E, E, E, E, E, E, E)
end
 
procedure game_is_drawn (board)
return *empty_fields(board) = 0
end
 
procedure game_won_by (board, player)
return (board.a == board.b == board.c == player) |
(board.d == board.e == board.f == player) |
(board.g == board.h == board.i == player) |
(board.a == board.d == board.g == player) |
(board.b == board.e == board.h == player) |
(board.c == board.f == board.i == player) |
(board.a == board.e == board.i == player) |
(board.g == board.e == board.c == player)
end
 
procedure game_over (board)
return game_is_drawn (board) | game_won_by (board, O) | game_won_by (board, X)
end
 
# -- players make their move on the board
# assume there is at least one empty square
 
procedure human_move (board, player)
choice := "z"
options := empty_fields (board)
# keep prompting until player selects a valid square
until member (options, choice) do {
writes ("Choose one of: ")
every writes (!options || " ")
writes ("\n> ")
choice := read ()
}
board[choice] := player
end
 
# pick and make a move at random from empty positions
procedure random_move (board, player)
board[?empty_fields(board)] := player
end
 
# -- manage the game play
procedure play_game ()
# hold procedures for players' move in variables
player_O := random_move
player_X := human_move
 
# randomly determine if human or computer moves first
if (?2 = 0)
then {
write ("Human plays first as O")
player_O := human_move
player_X := random_move
}
else write ("Computer plays first, human is X")
 
# set up the game to start
board := game_start ()
player := O
display_board (board, player)
# loop until the game is over, getting each player to move in turn
until game_over (board) do {
write (player || " to play next")
# based on player, prompt for the next move
if (player == O)
then (player_O (board, player))
else (player_X (board, player))
# change player to move
player := if (player == O) then X else O
display_board (board, player)
}
# finish by writing out result
if game_won_by (board, O)
then write ("O won")
else if game_won_by (board, X)
then write ("X won")
else write ("draw") # neither player won, so must be a draw
end
 
# -- get things started
procedure main ()
play_game ()
end
 

J[edit]

To subsequent j poster: replacing this entry is fine by me.

 
Note 'ttt adjudicates or plays'
 
use: markers ttt characters
 
characters represent the cell names.
 
markers is a length 3 character vector of the
characters to use for first and second player
followed by the opponent's mark.
'XOX' means X plays 1st, O is the other mark,
and the first strategy plays 1st.
'XOO' means X plays 1st, O is the other mark,
and the second strategy moves first.
 
The game is set up for the computer as the
first strategy (random), and human as second.
 
A standard use:
'XOX'ttt'abcdefghijkl'
 
Example game reformatted w/ emacs artist-mode
to fit your display:
 
'#-#'ttt'wersdfxcv'
w│e│r w│e│r .... -│e│r . -│e│#
─┼─┼─ . ─┼─┼─ .. ─┼─┼─ .. ─┼─┼─
s│d│f . s│#│f .. s│#│f .. -│#│f
─┼─┼─ .. ─┼─┼─ . ─┼─┼─ ... ─┼─┼─
x│c│v .. -│c│v . -│c│# .. -│c│#
d .. v .. r . VICTORY
w│e│r .. w│e│r .. -│e│# .
─┼─┼─ ... ─┼─┼─ .. ─┼─┼─ .
s│#│f ... s│#│f .. s│#│f .
─┼─┼─ .. ─┼─┼─ ... ─┼─┼─ ...
x│c│v -│c│# -│c│#
-->cell for -? -->cell for -? -->cell for -?
x w s
)

 
while=: conjunction def 'u ^: v ^:_' NB. j assumes while is a verb and needs to know while is a conjunction.
 
ttt=: [email protected]:(([email protected]:move) while undecided)@:[email protected]:prepare
 
blindfolded_variant=: [email protected]:[email protected]:(move while undecided)@:[email protected]:prepare
 
outcome=: {&(>;:'kitty VICTORY')@:won NB. (outcome does not pass along the state)
move=: post locate
undecided=: won nor full
prepare=: , [email protected]:] NB. form the state vector
 
Note 'locate'
is a monadic verb. y is the state vector.
returns the character of the chosen cell.
Generally:
locate=: second_strategy`[email protected](first = mark)
Simplified:
locate=: human_locate NB. human versus human
)

locate=: human_locate`[email protected](first = mark)
 
display=: show [: (1 1,:5 5)&(];.0)@:": [: <"0 fold
 
computer_locate=: [: [email protected]{. board -. marks NB. strategy: first available
computer_locate=: [: [email protected]({~ [email protected]:#) board -. marks NB. strategy: random
 
human_locate=: monad define
state=. y
m=. mark state
b=. board state
cells=. b -. marks state
show '-->cell for ' , m , '?'
whilst. cell [email protected]:e. cells do. cell =. {. (1!:1]1) , m end.
)
 
post=: 2&[email protected]:(3&{.)@:[ prepare [email protected]:[`((i.~ board)~)`([email protected]:[)}
 
mark=: {. NB. mark of the current player from state
marks=: 2&{. NB. extract both markers from state
board=: _9&{. NB. extract board from state
first=: 2&{ NB. extract first player from state
 
show=: [ smoutput
 
full=: 2 = #@:~.
won=: [email protected]:fold
fold=: 3 3 $ board
test=: [: any [: all [: infix_pairs_agree |:@:lines
 
lines=: , diagonal , [email protected]:|. , |:
diagonal=: (<0 1)&|:
all=: *./
any=: +./
nor=: 8 b.
infix_pairs_agree=: 2&(=/\)
 

Java[edit]

This version works in the terminal itself, and uses the numpad for data entry. The computer is unbeatable, but some lines can be removed to avoid that. There's also an override that thrown in, just for fun.

 
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Hashtable;
 
public class TicTacToe
{
public static void main(String[] args)
{
TicTacToe now=new TicTacToe();
now.startMatch();
}
 
private int[][] marks;
private int[][] wins;
private int[] weights;
private char[][] grid;
private final int knotcount=3;
private final int crosscount=4;
private final int totalcount=5;
private final int playerid=0;
private final int compid=1;
private final int truceid=2;
private final int playingid=3;
private String movesPlayer;
private byte override;
private char[][] overridegrid={{'o','o','o'},{'o','o','o'},{'o','o','o'}};
private char[][] numpad={{'7','8','9'},{'4','5','6'},{'1','2','3'}};
private Hashtable<Integer,Integer> crossbank;
private Hashtable<Integer,Integer> knotbank;
 
public void startMatch()
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.print("Start?(y/n):");
char choice='y';
try
{
choice=br.readLine().charAt(0);
}
catch(Exception e)
{
System.out.println(e.getMessage());
}
if(choice=='n'||choice=='N')
{
return;
}
 
System.out.println("Use a standard numpad as an entry grid, as so:\n ");
display(numpad);
System.out.println("Begin");
int playerscore=0;
int compscore=0;
do
{
int result=startGame();
if(result==playerid)
playerscore++;
else if(result==compid)
compscore++;
System.out.println("Score: Player-"+playerscore+" AI-"+compscore);
System.out.print("Another?(y/n):");
try
{
choice=br.readLine().charAt(0);
}
catch(Exception e)
{
System.out.println(e.getMessage());
}
 
}while(choice!='n'||choice=='N');
 
System.out.println("Game over.");
}
private void put(int cell,int player)
{
int i=-1,j=-1;;
switch(cell)
{
case 1:i=2;j=0;break;
case 2:i=2;j=1;break;
case 3:i=2;j=2;break;
case 4:i=1;j=0;break;
case 5:i=1;j=1;break;
case 6:i=1;j=2;break;
case 7:i=0;j=0;break;
case 8:i=0;j=1;break;
case 9:i=0;j=2;break;
default:display(overridegrid);return;
}
char mark='x';
if(player==0)
mark='o';
grid[i][j]=mark;
display(grid);
}
private int startGame()
{
init();
display(grid);
int status=playingid;
while(status==playingid)
{
put(playerMove(),0);
if(override==1)
{
System.out.println("O wins.");
return playerid;
}
status=checkForWin();
if(status!=playingid)
break;
try{Thread.sleep(1000);}catch(Exception e){System.out.print(e.getMessage());}
put(compMove(),1);
status=checkForWin();
}
return status;
}
private void init()
{
movesPlayer="";
override=0;
marks=new int[8][6];
wins=new int[][] //new int[8][3];
{
{7,8,9},
{4,5,6},
{1,2,3},
{7,4,1},
{8,5,2},
{9,6,3},
{7,5,3},
{9,5,1}
};
weights=new int[]{3,2,3,2,4,2,3,2,3};
grid=new char[][]{{' ',' ',' '},{' ',' ',' '},{' ',' ',' '}};
crossbank=new Hashtable<Integer,Integer>();
knotbank=new Hashtable<Integer,Integer>();
}
private void mark(int m,int player)
{
for(int i=0;i<wins.length;i++)
for(int j=0;j<wins[i].length;j++)
if(wins[i][j]==m)
{
marks[i][j]=1;
if(player==playerid)
marks[i][knotcount]++;
else
marks[i][crosscount]++;
marks[i][totalcount]++;
}
}
private void fixWeights()
{
for(int i=0;i<3;i++)
for(int j=0;j<3;j++)
if(marks[i][j]==1)
if(weights[wins[i][j]-1]!=Integer.MIN_VALUE)
weights[wins[i][j]-1]=Integer.MIN_VALUE;
 
for(int i=0;i<8;i++)
{
if(marks[i][totalcount]!=2)
continue;
if(marks[i][crosscount]==2)
{
int p=i,q=-1;
if(marks[i][0]==0)
q=0;
else if(marks[i][1]==0)
q=1;
else if(marks[i][2]==0)
q=2;
 
if(weights[wins[p][q]-1]!=Integer.MIN_VALUE)
{
weights[wins[p][q]-1]=6;
}
}
if(marks[i][knotcount]==2)
{
int p=i,q=-1;
if(marks[i][0]==0)
q=0;
else if(marks[i][1]==0)
q=1;
else if(marks[i][2]==0)
q=2;
 
if(weights[wins[p][q]-1]!=Integer.MIN_VALUE)
{
weights[wins[p][q]-1]=5;
}
}
}
}
private int compMove()
{
int cell=move();
System.out.println("Computer plays: "+cell);
//weights[cell-1]=Integer.MIN_VALUE;
return cell;
}
private int move()
{
int max=Integer.MIN_VALUE;
int cell=0;
for(int i=0;i<weights.length;i++)
if(weights[i]>max)
{
max=weights[i];
cell=i+1;
}
 
//This section ensures the computer never loses
//Remove it for a fair match
//Dirty kluge
if(movesPlayer.equals("76")||movesPlayer.equals("67"))
cell=9;
else if(movesPlayer.equals("92")||movesPlayer.equals("29"))
cell=3;
else if (movesPlayer.equals("18")||movesPlayer.equals("81"))
cell=7;
else if(movesPlayer.equals("73")||movesPlayer.equals("37"))
cell=4*((int)(Math.random()*2)+1);
else if(movesPlayer.equals("19")||movesPlayer.equals("91"))
cell=4+2*(int)(Math.pow(-1, (int)(Math.random()*2)));
 
mark(cell,1);
fixWeights();
crossbank.put(cell, 0);
return cell;
}
private int playerMove()
{
System.out.print("What's your move?: ");
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
int cell=0;
int okay=0;
while(okay==0)
{
try
{
cell=Integer.parseInt(br.readLine());
}
catch(Exception e)
{
System.out.println(e.getMessage());
}
if(cell==7494)
{
override=1;
return -1;
}
if((cell<1||cell>9)||weights[cell-1]==Integer.MIN_VALUE)
System.out.print("Invalid move. Try again:");
else
okay=1;
}
playerMoved(cell);
System.out.println();
return cell;
}
private void playerMoved(int cell)
{
movesPlayer+=cell;
mark(cell,0);
fixWeights();
knotbank.put(cell, 0);
}
private int checkForWin()
{
int crossflag=0,knotflag=0;
for(int i=0;i<wins.length;i++)
{
if(crossbank.containsKey(wins[i][0]))
if(crossbank.containsKey(wins[i][1]))
if(crossbank.containsKey(wins[i][2]))
{
crossflag=1;
break;
}
if(knotbank.containsKey(wins[i][0]))
if(knotbank.containsKey(wins[i][1]))
if(knotbank.containsKey(wins[i][2]))
{
knotflag=1;
break;
}
}
if(knotflag==1)
{
display(grid);
System.out.println("O wins.");
return playerid;
}
else if(crossflag==1)
{
display(grid);
System.out.println("X wins.");
return compid;
}
 
for(int i=0;i<weights.length;i++)
if(weights[i]!=Integer.MIN_VALUE)
return playingid;
System.out.println("Truce");
 
return truceid;
}
private void display(char[][] grid)
{
for(int i=0;i<3;i++)
{
System.out.println("\n-------");
System.out.print("|");
for(int j=0;j<3;j++)
System.out.print(grid[i][j]+"|");
}
System.out.println("\n-------");
}
}
 
Start?(y/n):y
Use a standard numpad as an entry grid, as so:
-------
|7|8|9|
-------
|4|5|6|
-------
|1|2|3|
-------
Begin

-------
| | | |
-------
| | | |
-------
| | | |
-------
What's your move?: 4

-------
| | | |
-------
|o| | |
-------
| | | |
-------

(...)

Computer plays: 7
-------
|x| |o|
-------
|o|x|o|
-------
|x|o|x|
-------
X wins.

Score: Player-0 AI-1
Another?(y/n):n
Game over.


This version uses javax.swing.

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.logging.Logger;
/**
 
* TicTacToe Application
* @author Steve Robinson
* @version 1.0
*/

class TicTacToeFrame extends JFrame
{
JButton [][] buttons= new JButton[3][3];
JTextField statusBar;
GamePanel panel;
Integer turn;
GameListener listener=new GameListener();
Integer count;
public TicTacToeFrame()
{
setLayout(new BorderLayout());
panel=new GamePanel();
add(panel,BorderLayout.CENTER);
statusBar=new JTextField("Player1's Turn");
statusBar.setEditable(false);
add(statusBar,BorderLayout.SOUTH);
setTitle("Tic Tac Toe!");
setVisible(true);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(400,400,300,300);
}
class GamePanel extends JPanel
{
public GamePanel()
{
setLayout(new GridLayout(3,3));
turn =1;
count=0;
for(int i=0;i<3;i++)
for(int j=0;j<3;j++) {
buttons[i][j]=new JButton();
buttons[i][j].putClientProperty("INDEX", new Integer[]{i,j});
buttons[i][j].putClientProperty("OWNER", null);
buttons[i][j].addActionListener(listener);
add(buttons[i][j]);
}
}
}
class GameListener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
count++;
JButton b=(JButton)e.getSource();
Integer[]index=(Integer[]) b.getClientProperty("INDEX");
//System.out.println(turn); //turn // //System.out.println("["+index[0]+"]"+"["+index[1]+"]"); //
b.putClientProperty("OWNER", turn);
Icon ico=new ImageIcon(turn.toString()+".gif");
b.setIcon(ico);
b.setEnabled(false);
boolean result=checkVictoryCondition(index);
if(result)
{
JOptionPane.showMessageDialog(null, "Player "+turn.toString()+" Wins");
initComponents();
}
else
{
if(turn==1)
{
turn=2;
statusBar.setText("Player2's Turn");
}
else
{
turn=1;
statusBar.setText("Player1's Turn");
}
}
if(count==9)
{
JOptionPane.showMessageDialog(null, "Match is a draw!");
initComponents();
}
}
Integer getOwner(JButton b)
{
return (Integer)b.getClientProperty("OWNER");
}
//PrintButtonMap for Diagnostics
void printbuttonMap(Integer [][]bMap)
{
for(int i=0;i for(int j=0;j System.out.print(bMap[i][j]+" ");
System.out.println("");
}
}
boolean checkVictoryCondition(Integer [] index)
{
/*Integer[][]buttonMap=new Integer[][] {
 
{ getOwner(buttons[0][0]),getOwner(buttons[0][1]),getOwner(buttons[0][2])},
 
{ getOwner(buttons[1][0]),getOwner(buttons[1][1]),getOwner(buttons[1][2])},
 
{ getOwner(buttons[2][0]),getOwner(buttons[2][1]),getOwner(buttons[2][2])}
};
printbuttonMap(buttonMap); */

Integer a=index[0];
Integer b=index[1];
int i;
//check row
for(i=0;i<3;i++) {
if(getOwner(buttons[a][i])!=getOwner(buttons[a][b]))
break;
}
if(i==3)
return true;
//check column
for(i=0;i<3;i++) {
if(getOwner(buttons[i][b])!=getOwner(buttons[a][b]))
break;
}
if(i==3)
return true;
//check diagonal
if((a==2&&b==2)||(a==0&&b==0)||(a==1&&b==1)||(a==0&&b==2)||(a==2&&b==0))
{
//left diagonal
for(i=0;i if(getOwner(buttons[i][i])!=getOwner(buttons[a][b]))
break;
if(i==3)
return true;
//right diagonal
if((getOwner(buttons[0][2])==getOwner(buttons[a][b]))&&(getOwner(buttons[1][1])==getOwner(buttons[a][b]))&&(getOwner(buttons[2][0])==getOwner(buttons[a][b])))
return true;
}
return false;
}
}
void initComponents()
{
for(int i=0;i<3;i++)
for(int j=0;j<3;j++) {
buttons[i][j].putClientProperty("INDEX", new Integer[]{i,j});
buttons[i][j].putClientProperty("OWNER",null);
buttons[i][j].setIcon(null);
buttons[i][j].setEnabled(true);
turn=1;
count=0;
statusBar.setText("Player1's Turn");
}
}
}
class TicTacToe {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable(){
public void run()
{
TicTacToeFrame frame=new TicTacToeFrame();
}
});
}
}
 

Graphical Java Example

 
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
 
 
//Make sure the name of the class is the same as the .java file name.
//If you change the class name you should change the class object name in runGUI method
public class ticTacToeCallum implements ActionListener {
 
static JFrame frame;
static JPanel contentPane;
static JLabel lblEnterFirstPlayerName, lblEnterSecondPlayerName, lblFirstPlayerScore, lblSecondPlayerScore;
static JButton btnButton1, btnButton2, btnButton3, btnButton4, btnButton5, btnButton6, btnButton7, btnButton8, btnButton9, btnClearBoard, btnClearAll, btnCloseGame;
static JTextField txtEnterFirstPlayerName, txtEnterSecondPlayerName;
static Icon imgicon = new ImageIcon("saveIcon.JPG");
 
Font buttonFont = new Font("Arial", Font.PLAIN, 20);
 
 
//to adjust the frame size change the values in pixels
static int width = 600;
static int length = 400;
static int firstPlayerScore = 0;
static int secondPlayerScore = 0;
static int playerTurn = 1;
static int roundComplete = 0;
static int button1 = 1, button2 = 1, button3 = 1, button4 = 1, button5 = 1, button6 = 1, button7 = 1, button8 = 1, button9 = 1; // 1 is true, 0 is false
 
 
public ticTacToeCallum(){
 
frame = new JFrame("Tic Tac Toe ^_^");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
contentPane = new JPanel();
contentPane.setLayout(new GridLayout(6, 3, 10, 10));
contentPane.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
 
btnButton1 = new JButton("");
btnButton1.setFont(buttonFont);
btnButton1.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnButton1.setIcon(imgicon);
btnButton1.setActionCommand("CLICK1");
btnButton1.addActionListener(this);
contentPane.add(btnButton1);
 
btnButton2 = new JButton("");
btnButton2.setFont(buttonFont);
btnButton2.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnButton2.setIcon(imgicon);
btnButton2.setActionCommand("CLICK2");
btnButton2.addActionListener(this);
contentPane.add(btnButton2);
 
btnButton3 = new JButton("");
btnButton3.setFont(buttonFont);
btnButton3.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnButton3.setIcon(imgicon);
btnButton3.setActionCommand("CLICK3");
btnButton3.addActionListener(this);
contentPane.add(btnButton3);
 
btnButton4 = new JButton("");
btnButton4.setFont(buttonFont);
btnButton4.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnButton4.setIcon(imgicon);
btnButton4.setActionCommand("CLICK4");
btnButton4.addActionListener(this);
contentPane.add(btnButton4);
 
btnButton5 = new JButton("");
btnButton5.setFont(buttonFont);
btnButton5.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnButton5.setIcon(imgicon);
btnButton5.setActionCommand("CLICK5");
btnButton5.addActionListener(this);
contentPane.add(btnButton5);
 
btnButton6 = new JButton("");
btnButton6.setFont(buttonFont);
btnButton6.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnButton6.setIcon(imgicon);
btnButton6.setActionCommand("CLICK6");
btnButton6.addActionListener(this);
contentPane.add(btnButton6);
 
btnButton7 = new JButton("");
btnButton7.setFont(buttonFont);
btnButton7.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnButton7.setIcon(imgicon);
btnButton7.setActionCommand("CLICK7");
btnButton7.addActionListener(this);
contentPane.add(btnButton7);
 
btnButton8 = new JButton("");
btnButton8.setFont(buttonFont);
btnButton8.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnButton8.setIcon(imgicon);
btnButton8.setActionCommand("CLICK8");
btnButton8.addActionListener(this);
contentPane.add(btnButton8);
 
btnButton9 = new JButton("");
btnButton9.setFont(buttonFont);
btnButton9.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnButton9.setIcon(imgicon);
btnButton9.setActionCommand("CLICK9");
btnButton9.addActionListener(this);
contentPane.add(btnButton9);
 
lblEnterFirstPlayerName = new JLabel("Enter First Player's Name");
contentPane.add(lblEnterFirstPlayerName);
 
txtEnterFirstPlayerName = new JTextField("");
contentPane.add(txtEnterFirstPlayerName);
 
lblFirstPlayerScore = new JLabel("Score: " + firstPlayerScore);
contentPane.add(lblFirstPlayerScore);
 
lblEnterSecondPlayerName = new JLabel("Enter Second Player's Name");
contentPane.add(lblEnterSecondPlayerName);
 
txtEnterSecondPlayerName = new JTextField("");
contentPane.add(txtEnterSecondPlayerName);
 
lblSecondPlayerScore = new JLabel("Score: " + secondPlayerScore);
contentPane.add(lblSecondPlayerScore);
 
btnClearBoard = new JButton("Clear Board");
btnClearBoard.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnClearBoard.setIcon(imgicon);
btnClearBoard.setActionCommand("CLICKClearBoard");
btnClearBoard.addActionListener(this);
contentPane.add(btnClearBoard);
 
btnClearAll = new JButton("Clear All");
btnClearAll.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnClearAll.setIcon(imgicon);
btnClearAll.setActionCommand("CLICKClearAll");
btnClearAll.addActionListener(this);
contentPane.add(btnClearAll);
 
btnCloseGame = new JButton("Close Game");
btnCloseGame.setAlignmentX(JButton.CENTER_ALIGNMENT);
btnCloseGame.setIcon(imgicon);
btnCloseGame.setActionCommand("CLICKCloseGame");
btnCloseGame.addActionListener(this);
contentPane.add(btnCloseGame);
 
frame.setContentPane(contentPane);
frame.pack();
frame.setSize(width,length);
frame.setVisible(true);
 
}
 
public void actionPerformed(ActionEvent event) {
String eventName = event.getActionCommand();
if (eventName.equals("CLICK1")) {
if (button1 == 1){
if (playerTurn == 1){
btnButton1.setForeground(Color.RED);
btnButton1.setText("X");
playerTurn = 2;
button1 = 0;
} else if (playerTurn == 2) {
btnButton1.setForeground(Color.GREEN);
btnButton1.setText("O");
playerTurn = 1;
button1 = 0;
}
}
} else if (eventName.equals ("CLICK2")) {
if (button2 == 1){
if (playerTurn == 1){
btnButton2.setForeground(Color.RED);
btnButton2.setText("X");
playerTurn = 2;
button2 = 0;
} else if (playerTurn == 2) {
btnButton2.setForeground(Color.GREEN);
btnButton2.setText("O");
playerTurn = 1;
button2 = 0;
}
}
} else if (eventName.equals ("CLICK3")) {
if (button3 == 1){
if (playerTurn == 1){
btnButton3.setForeground(Color.RED);
btnButton3.setText("X");
playerTurn = 2;
button3 = 0;
} else if (playerTurn == 2) {
btnButton3.setForeground(Color.GREEN);
btnButton3.setText("O");
playerTurn = 1;
button3 = 0;
}
}
} else if (eventName.equals ("CLICK4")) {
if (button4 == 1){
if (playerTurn == 1){
btnButton4.setForeground(Color.RED);
btnButton4.setText("X");
playerTurn = 2;
button4 = 0;
} else if (playerTurn == 2) {
btnButton4.setForeground(Color.GREEN);
btnButton4.setText("O");
playerTurn = 1;
button4 = 0;
}
}
} else if (eventName.equals ("CLICK5")) {
if (button5 == 1){
if (playerTurn == 1){
btnButton5.setForeground(Color.RED);
btnButton5.setText("X");
playerTurn = 2;
button5 = 0;
} else if (playerTurn == 2) {
btnButton5.setForeground(Color.GREEN);
btnButton5.setText("O");
playerTurn = 1;
button5 = 0;
}
}
} else if (eventName.equals ("CLICK6")) {
if (button6 == 1){
if (playerTurn == 1){
btnButton6.setForeground(Color.RED);
btnButton6.setText("X");
playerTurn = 2;
button6 = 0;
} else if (playerTurn == 2) {
btnButton6.setForeground(Color.GREEN);
btnButton6.setText("O");
playerTurn = 1;
button6 = 0;
}
}
} else if (eventName.equals ("CLICK7")) {
if (button7 == 1){
if (playerTurn == 1){
btnButton7.setForeground(Color.RED);
btnButton7.setText("X");
playerTurn = 2;
button7 = 0;
} else if (playerTurn == 2) {
btnButton7.setForeground(Color.GREEN);
btnButton7.setText("O");
playerTurn = 1;
button7 = 0;
}
}
} else if (eventName.equals ("CLICK8")) {
if (button8 == 1){
if (playerTurn == 1){
btnButton8.setForeground(Color.RED);
btnButton8.setText("X");
playerTurn = 2;
button8 = 0;
} else if (playerTurn == 2) {
btnButton8.setForeground(Color.GREEN);
btnButton8.setText("O");
playerTurn = 1;
button8 = 0;
}
}
} else if (eventName.equals ("CLICK9")) {
if (button9 == 1){
if (playerTurn == 1){
btnButton9.setForeground(Color.RED);
btnButton9.setText("X");
playerTurn = 2;
button9 = 0;
} else if (playerTurn == 2) {
btnButton9.setForeground(Color.GREEN);
btnButton9.setText("O");
playerTurn = 1;
button9 = 0;
}
}
} else if (eventName.equals ("CLICKClearBoard")) {
 
btnButton1.setText("");
btnButton2.setText("");
btnButton3.setText("");
btnButton4.setText("");
btnButton5.setText("");
btnButton6.setText("");
btnButton7.setText("");
btnButton8.setText("");
btnButton9.setText("");
 
button1 = 1;
button2 = 1;
button3 = 1;
button4 = 1;
button5 = 1;
button6 = 1;
button7 = 1;
button8 = 1;
button9 = 1;
 
playerTurn = 1;
 
roundComplete = 0;
 
} else if (eventName.equals ("CLICKClearAll")) {
 
btnButton1.setText("");
btnButton2.setText("");
btnButton3.setText("");
btnButton4.setText("");
btnButton5.setText("");
btnButton6.setText("");
btnButton7.setText("");
btnButton8.setText("");
btnButton9.setText("");
 
firstPlayerScore = 0;
lblFirstPlayerScore.setText("Score: " + firstPlayerScore);
secondPlayerScore = 0;
lblSecondPlayerScore.setText("Score: " + secondPlayerScore);
 
txtEnterFirstPlayerName.setText("");
txtEnterSecondPlayerName.setText("");
 
button1 = 1;
button2 = 1;
button3 = 1;
button4 = 1;
button5 = 1;
button6 = 1;
button7 = 1;
button8 = 1;
button9 = 1;
 
playerTurn = 1;
 
roundComplete = 0;
 
} else if (eventName.equals ("CLICKCloseGame")) {
System.exit(0);
}
score();
}
 
 
public static void score(){
if (roundComplete == 0){
if (btnButton1.getText().equals(btnButton2.getText()) && btnButton1.getText().equals(btnButton3.getText())){
if (btnButton1.getText().equals("X")){
firstPlayerScore += 1;
lblFirstPlayerScore.setText("Score: " + firstPlayerScore);
roundComplete = 1;
} else if (btnButton1.getText().equals("O")){
secondPlayerScore += 1;
lblSecondPlayerScore.setText("Score: " + secondPlayerScore);
roundComplete = 1;
}
}
if (btnButton1.getText().equals(btnButton4.getText()) && btnButton1.getText().equals(btnButton7.getText())){
if (btnButton1.getText().equals("X")){
firstPlayerScore += 1;
lblFirstPlayerScore.setText("Score: " + firstPlayerScore);
roundComplete = 1;
} else if (btnButton1.getText().equals("O")){
secondPlayerScore += 1;
lblSecondPlayerScore.setText("Score: " + secondPlayerScore);
roundComplete = 1;
}
}
if (btnButton1.getText().equals(btnButton5.getText()) && btnButton1.getText().equals(btnButton9.getText())){
if (btnButton1.getText().equals("X")){
firstPlayerScore += 1;
lblFirstPlayerScore.setText("Score: " + firstPlayerScore);
roundComplete = 1;
} else if (btnButton1.getText().equals("O")){
secondPlayerScore += 1;
lblSecondPlayerScore.setText("Score: " + secondPlayerScore);
roundComplete = 1;
}
}
if (btnButton7.getText().equals(btnButton8.getText()) && btnButton7.getText().equals(btnButton9.getText())){
if (btnButton7.getText().equals("X")){
firstPlayerScore += 1;
lblFirstPlayerScore.setText("Score: " + firstPlayerScore);
roundComplete = 1;
} else if (btnButton7.getText().equals("O")){
secondPlayerScore += 1;
lblSecondPlayerScore.setText("Score: " + secondPlayerScore);
roundComplete = 1;
}
}
if (btnButton7.getText().equals(btnButton5.getText()) && btnButton7.getText().equals(btnButton3.getText())){
if (btnButton7.getText().equals("X")){
firstPlayerScore += 1;
lblFirstPlayerScore.setText("Score: " + firstPlayerScore);
roundComplete = 1;
} else if (btnButton7.getText().equals("O")){
secondPlayerScore += 1;
lblSecondPlayerScore.setText("Score: " + secondPlayerScore);
roundComplete = 1;
}
}
if (btnButton3.getText().equals(btnButton6.getText()) && btnButton3.getText().equals(btnButton9.getText())){
if (btnButton3.getText().equals("X")){
firstPlayerScore += 1;
lblFirstPlayerScore.setText("Score: " + firstPlayerScore);
roundComplete = 1;
} else if (btnButton3.getText().equals("O")){
secondPlayerScore += 1;
lblSecondPlayerScore.setText("Score: " + secondPlayerScore);
roundComplete = 1;
}
}
if (btnButton4.getText().equals(btnButton5.getText()) && btnButton4.getText().equals(btnButton6.getText())){
if (btnButton4.getText().equals("X")){
firstPlayerScore += 1;
lblFirstPlayerScore.setText("Score: " + firstPlayerScore);
roundComplete = 1;
} else if (btnButton4.getText().equals("O")){
secondPlayerScore += 1;
lblSecondPlayerScore.setText("Score: " + secondPlayerScore);
roundComplete = 1;
}
}
if (btnButton2.getText().equals(btnButton5.getText()) && btnButton2.getText().equals(btnButton8.getText())){
if (btnButton2.getText().equals("X")){
firstPlayerScore += 1;
lblFirstPlayerScore.setText("Score: " + firstPlayerScore);
roundComplete = 1;
} else if (btnButton2.getText().equals("O")){
secondPlayerScore += 1;
lblSecondPlayerScore.setText("Score: " + secondPlayerScore);
roundComplete = 1;
}
}
}
if (roundComplete == 1){
button1 = 0;
button2 = 0;
button3 = 0;
button4 = 0;
button5 = 0;
button6 = 0;
button7 = 0;
button8 = 0;
button9 = 0;
}
}
 
/**
* Create and show the GUI.
*/

private static void runGUI() {
ticTacToeCallum greeting = new ticTacToeCallum();
}
 
 
 
//Do not change this method
public static void main(String[] args) {
/* Methods that create and show a GUI should be run from an event-dispatching thread */
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
runGUI();
}
});
}
}
 

The following program may be executed for a player-against-player game.

 
import javax.swing.*;
import javax.swing.border.Border;
import java.awt.*;
 
public class TicTacToe {
private static int turnNumber = 0;
private static final JPanel panel = new JPanel();
private static final JTextField ta = new JTextField("Player A's Turn (X)");
private static final JButton r1c1 = new JButton("");
private static final JButton r1c2 = new JButton("");
private static final JButton r1c3 = new JButton("");
private static final JButton r2c1 = new JButton("");
private static final JButton r2c2 = new JButton("");
private static final JButton r2c3 = new JButton("");
private static final JButton r3c1 = new JButton("");
private static final JButton r3c2 = new JButton("");
private static final JButton r3c3 = new JButton("");
private static final JButton restart = new JButton("New Game");
private static final JPanel startMain = new JPanel();
 
public static void main(String[]args){
JFrame frame = new JFrame("Tic Tac Toe");
frame.setSize(600,650);
ta.setEditable(false);
restart.addActionListener(e -> {
enableAll();
ta.setText("Player A's Turn (X)");
});
r1c1.setSize(67,67);
r1c1.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
r1c1.addActionListener(e -> {
turnNumber++;
if(turnNumber % 2 == 0){
r1c1.setText("O");
r1c1.setEnabled(false);
ta.setText("Player A's Turn (X)");
}else{
r1c1.setText("X");
r1c1.setEnabled(false);
ta.setText("Player B's Turn (O)");
}
checkWin();
});
r1c2.setSize(67,67);
r1c2.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
r1c2.addActionListener(e -> {
turnNumber++;
if(turnNumber % 2 == 0){
r1c2.setText("O");
r1c2.setEnabled(false);
ta.setText("Player A's Turn (X)");
}else{
r1c2.setText("X");
r1c2.setEnabled(false);
ta.setText("Player B's Turn (O)");
}
checkWin();
});
r1c3.setSize(67,67);
r1c3.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
r1c3.addActionListener(e -> {
turnNumber++;
if(turnNumber % 2 == 0){
r1c3.setText("O");
r1c3.setEnabled(false);
ta.setText("Player A's Turn (X)");
}else{
r1c3.setText("X");
r1c3.setEnabled(false);
ta.setText("Player B's Turn (O)");
}
checkWin();
});
r2c1.setSize(67,67);
r2c1.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
r2c1.addActionListener(e -> {
turnNumber++;
if(turnNumber % 2 == 0){
r2c1.setText("O");
r2c1.setEnabled(false);
ta.setText("Player A's Turn (X)");
}else{
r2c1.setText("X");
r2c1.setEnabled(false);
ta.setText("Player B's Turn (O)");
}
checkWin();
});
r2c2.setSize(67,67);
r2c2.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
r2c2.addActionListener(e -> {
turnNumber++;
if(turnNumber % 2 == 0){
r2c2.setText("O");
r2c2.setEnabled(false);
ta.setText("Player A's Turn (X)");
}else{
r2c2.setText("X");
r2c2.setEnabled(false);
ta.setText("Player B's Turn (O)");
}
checkWin();
});
r2c3.setSize(67,67);
r2c3.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
r2c3.addActionListener(e -> {
turnNumber++;
if(turnNumber % 2 == 0){
r2c3.setText("O");
r2c3.setEnabled(false);
ta.setText("Player A's Turn (X)");
}else{
r2c3.setText("X");
r2c3.setEnabled(false);
ta.setText("Player B's Turn (O)");
}
checkWin();
});
r3c1.setSize(67,67);
r3c1.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
r3c1.addActionListener(e -> {
turnNumber++;
if(turnNumber % 2 == 0){
r3c1.setText("O");
r3c1.setEnabled(false);
ta.setText("Player A's Turn (X)");
}else{
r3c1.setText("X");
r3c1.setEnabled(false);
ta.setText("Player B's Turn (O)");
}
checkWin();
});
r3c2.setSize(67,67);
r3c2.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
r3c2.addActionListener(e -> {
turnNumber++;
if(turnNumber % 2 == 0){
r3c2.setText("O");
r3c2.setEnabled(false);
ta.setText("Player A's Turn (X)");
}else{
r3c2.setText("X");
r3c2.setEnabled(false);
ta.setText("Player B's Turn (O)");
}
checkWin();
});
r3c3.setSize(67,67);
r3c3.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
r3c3.addActionListener(e -> {
turnNumber++;
if(turnNumber % 2 == 0){
r3c3.setText("O");
r3c3.setEnabled(false);
ta.setText("Player A's Turn (X)");
}else{
r3c3.setText("X");
r3c3.setEnabled(false);
ta.setText("Player B's Turn (O)");
}
checkWin();
});
panel.setLayout(new GridLayout(3,3));
 
panel.add(r1c1);
panel.add(r1c2);
panel.add(r1c3);
panel.add(r2c1);
panel.add(r2c2);
panel.add(r2c3);
panel.add(r3c1);
panel.add(r3c2);
panel.add(r3c3);
startMain.setLayout(new GridLayout(5,5));
JButton start = new JButton("Start");
JLabel main = new JLabel("Tic Tac Toe", SwingConstants.CENTER);
main.setFont(new Font("Trebuchet MS", Font.PLAIN, 70));
main.setSize(400,400);
startMain.add(main);
startMain.add(start);
frame.add(startMain);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
start.addActionListener(e -> {
startMain.setVisible(false);
frame.add(restart, BorderLayout.PAGE_START);
frame.add(ta, BorderLayout.PAGE_END);
frame.add(panel, BorderLayout.CENTER);
});
}
public static void checkWin(){
if(r1c1.getText().equals("X") && r1c2.getText().equals("X") && r1c3.getText().equals("X")){
ta.setText("Player A Won! (X)");
disableAll();
}else if(r1c1.getText().equals("O") && r1c2.getText().equals("O") && r1c3.getText().equals("O")){
ta.setText("Player B Won! (O)");
disableAll();
}else if(r1c1.getText().equals("X") && r2c2.getText().equals("X") && r3c3.getText().equals("X")){
ta.setText("Player A Won! (X)");
disableAll();
}else if(r1c1.getText().equals("O") && r2c2.getText().equals("O") && r3c3.getText().equals("O")){
ta.setText("Player B Won! (O)");
disableAll();
}else if(r1c1.getText().equals("X") && r2c1.getText().equals("X") && r3c1.getText().equals("X")){
ta.setText("Player A Won! (X)");
disableAll();
}else if(r1c1.getText().equals("O") && r2c1.getText().equals("O") && r3c1.getText().equals("O")){
ta.setText("Player B Won! (O)");
disableAll();
}else if(r2c1.getText().equals("X") && r2c2.getText().equals("X") && r2c3.getText().equals("X")){
ta.setText("Player A Won! (X)");
disableAll();
}else if(r2c1.getText().equals("O") && r2c2.getText().equals("O") && r2c3.getText().equals("O")){
ta.setText("Player B Won! (O)");
disableAll();
}else if(r1c2.getText().equals("X") && r2c2.getText().equals("X") && r3c2.getText().equals("X")){
ta.setText("Player A Won! (X)");
disableAll();
}else if(r1c2.getText().equals("O") && r2c2.getText().equals("O") && r3c2.getText().equals("O")){
ta.setText("Player B Won! (O)");
disableAll();
}else if(r1c3.getText().equals("X") && r2c3.getText().equals("X") && r3c3.getText().equals("X")){
ta.setText("Player A Won! (X)");
disableAll();
}else if(r1c3.getText().equals("O") && r2c3.getText().equals("O") && r3c3.getText().equals("O")){
ta.setText("Player B Won! (O)");
disableAll();
}else if(r3c1.getText().equals("X") && r3c2.getText().equals("X") && r3c3.getText().equals("X")){
ta.setText("Player A Won! (X)");
disableAll();
}else if(r3c1.getText().equals("O") && r3c2.getText().equals("O") && r3c3.getText().equals("O")){
ta.setText("Player B Won! (O)");
disableAll();
}else if(r3c1.getText().equals("X") && r2c2.getText().equals("X") && r1c3.getText().equals("X")){
ta.setText("Player A Won! (X)");
disableAll();
}else if(r3c1.getText().equals("O") && r2c2.getText().equals("O") && r1c3.getText().equals("O")){
ta.setText("Player B Won! (O)");
disableAll();
}else if(!r1c1.isEnabled() && !r1c2.isEnabled() && !r1c3.isEnabled() && !r2c1.isEnabled() && !r2c2.isEnabled() && !r2c3.isEnabled() && !r3c1.isEnabled() && !r3c2.isEnabled() && !r3c3.isEnabled()){
ta.setText("Draw!");
disableAll();
}
}
public static void disableAll(){
r1c1.setEnabled(false);
r1c2.setEnabled(false);
r1c3.setEnabled(false);
r2c1.setEnabled(false);
r2c2.setEnabled(false);
r2c3.setEnabled(false);
r3c1.setEnabled(false);
r3c2.setEnabled(false);
r3c3.setEnabled(false);
}
 
public static void enableAll(){
turnNumber = 0;
r1c1.setEnabled(true);
r1c2.setEnabled(true);
r1c3.setEnabled(true);
r2c1.setEnabled(true);
r2c2.setEnabled(true);
r2c3.setEnabled(true);
r3c1.setEnabled(true);
r3c2.setEnabled(true);
r3c3.setEnabled(true);
r1c1.setText("");
r1c2.setText("");
r1c3.setText("");
r2c1.setText("");
r2c2.setText("");
r2c3.setText("");
r3c1.setText("");
r3c2.setText("");
r3c3.setText("");
panel.setEnabled(true);
}
}
 

JavaScript[edit]

HTML5 Canvas implementation. Should play perfectly or near-perfectly.

 
<!DOCTYPE html>
 
<html>
 
<head>
<meta charset="utf-8" />
<title>TicTacToe</title>
</head>
 
<body>
<canvas id="canvas" width="400" height="400"></canvas>
 
<script>
//All helper functions
isBetween = (num, a, b) => {
return num >= a && num <= b;
}
 
randInt = (low, high) => {
return Math.floor(Math.random() * (high - low + 1)) + low;
}
 
choice = arr => {
return arr[randInt(0, arr.length - 1)];
}
 
//Checks if every value in an array equals an item
equals = (arr, item) => {
return arr.filter(a => {
return a === item;
}).length === arr.length;
}
 
//Returns number of items in array that equal an item
equallen = (arr, item) => {
return arr.filter(a => {
return a === item;
}).length
}
 
//Checks if any value in the array equals an item
equalanyof = (arr, item) => {
return equallen(arr, item) > 0;
}
 
//Should be scalable, but it uses default elements for calculations and tracking
let canvas = document.getElementById("canvas");
let ctx = canvas.getContext("2d");
const width = canvas.width;
const blockSize = canvas.width / 3;
const lineSize = blockSize / 5;
 
//Draws background
ctx.fillStyle = "rgb(225, 225, 225)";
ctx.fillRect(0, 0, 400, 400);
 
//Title page
ctx.fillStyle = "rgb(0, 0, 0)";
ctx.font = width / (250 / 17) + "px Arial"; //34
ctx.textAlign = "center";
ctx.fillText("Tic Tac Toe", width / 2, width / (2 + 2 / 3)); //200, 150
 
//Button for starting
ctx.fillStyle = "rgb(200, 200, 200)";
ctx.fillRect(width / 3.2, width / 2, width / (2 + 2 / 3), width / 8); //125, 200, 150, 50
ctx.fillStyle = "rgb(0, 0, 0)";
ctx.font = width / (200 / 9) + "px Arial"; //18
ctx.fillText("Start", width / 2, width / (40 / 23)); //200, 230
 
//Uses an array so a forEach loop can scan it for the correct tile
let tileArray = []; //Contains all tiles
let available = []; //Contains only available tiles
 
class Tile {
constructor(x, y) {
this.x = x * blockSize;
this.y = y * blockSize;
this.state = "none";
tileArray.push(this);
available.push(this);
}
 
draw() {
ctx.strokeStyle = "rgb(175, 175, 175)";
ctx.lineWidth = blockSize / 10;
 
if (this.state === "X") {
ctx.beginPath();
ctx.moveTo(this.x + blockSize / 4, this.y + blockSize / 4);
ctx.lineTo(this.x + blockSize / (4 / 3), this.y + blockSize / (4 / 3));
ctx.moveTo(this.x + blockSize / 4, this.y + blockSize / (4 / 3));
ctx.lineTo(this.x + blockSize / (4 / 3), this.y + blockSize / 4);
ctx.stroke();
} else if (this.state === "O") {
ctx.beginPath();
ctx.arc(this.x + blockSize / 2, this.y + blockSize / 2, blockSize / 4, 0, 2 * Math.PI);
ctx.stroke();
}
 
//Removes this from the available array
const ind = available.indexOf(this);
available = available.slice(0, ind).concat(available.slice(ind + 1, available.length));
}
}
 
 
//Defines the game
let game = {
state: "start",
turn: "Player",
player: "X",
opp: "O"
}
 
//Generates tiles
for (let x = 0; x < 3; x++) {
for (let y = 0; y < 3; y++) {
new Tile(x, y);
}
}
 
//Gets the mouse position
getMousePos = evt => {
let rect = canvas.getBoundingClientRect();
return {
x: evt.clientX - rect.left,
y: evt.clientY - rect.top
}
}
 
//Checks for win conditions
checkCondition = () => {
//Local variables are created to make access easier
let as = tileArray[0].state;
let bs = tileArray[1].state;
let cs = tileArray[2].state;
let ds = tileArray[3].state;
let es = tileArray[4].state;
let fs = tileArray[5].state;
let gs = tileArray[6].state;
let hs = tileArray[7].state;
let is = tileArray[8].state;
 
//Equals function checks if each value in the array has a state of X or O
if (equals([as, bs, cs], "X") || equals([ds, es, fs], "X") || equals([gs, hs, is], "X") ||
equals([as, ds, gs], "X") || equals([bs, es, hs], "X") || equals([cs, fs, is], "X") ||
equals([as, es, is], "X") || equals([cs, es, gs], "X")) {
alert("Player wins!");
game.state = "over";
} else if (equals([as, bs, cs], "O") || equals([ds, es, fs], "O") || equals([gs, hs, is], "O") ||
equals([as, ds, gs], "O") || equals([bs, es, hs], "O") || equals([cs, fs, is], "O") ||
equals([as, es, is], "O") || equals([cs, es, gs], "O")) {
alert("Opponent wins!");
game.state = "over";
//It is a tie if none of the above conditions are fulfilled and there are no available tiles
} else if (available.length === 0) {
alert("It's a tie!");
game.state = "over";
}
}
 
//Controls the opponent. Uses many nested switches/if-else for efficiency
oppTurn = () => {
if (game.state === "game") {
let tile = 0;
 
//Similar local variables as the win checker
let at = tileArray[0].state;
let bt = tileArray[1].state;
let ct = tileArray[2].state;
let dt = tileArray[3].state;
let et = tileArray[4].state;
let ft = tileArray[5].state;
let gt = tileArray[6].state;
let ht = tileArray[7].state;
let it = tileArray[8].state;
let all = [at, bt, ct, dt, et, ft, gt, ht, it];
 
/*The AI will automatically win if possible
I considered using a filter based system, but it was ugly and
inelegant, and also redundant
I used a nested if-else instead
Equallen checks how many values in the array equal the given value*/

if (equallen(all, "O") >= 2) {
if (equallen([at, bt, ct], "O") === 2 && equallen([at, bt, ct], "X") === 0) {
if (at === "none") {
tile = tileArray[0];
} else if (bt === "none") {
tile = tileArray[1];
} else if (ct === "none") {
tile = tileArray[2];
}
} else if (equallen([dt, et, ft], "O") === 2 && equallen([dt, et, ft], "X") === 0) {
if (dt === "none") {
tile = tileArray[3];
} else if (et === "none") {
tile = tileArray[4];
} else if (ft === "none") {
tile = tileArray[5];
}
} else if (equallen([gt, ht, it], "O") === 2 && equallen([gt, ht, it], "X") === 0) {
if (gt === "none") {
tile = tileArray[6];
} else if (ht === "none") {
tile = tileArray[7];
} else if (it === "none") {
tile = tileArray[8];
}
} else if (equallen([at, dt, gt], "O") === 2 && equallen([at, dt, gt], "X") === 0) {
if (at === "none") {
tile = tileArray[0];
} else if (dt === "none") {
tile = tileArray[3];
} else if (gt === "none") {
tile = tileArray[6];
}
} else if (equallen([bt, et, ht], "O") === 2 && equallen([bt, et, ht], "X") === 0) {
if (bt === "none") {
tile = tileArray[1];
} else if (et === "none") {
tile = tileArray[4];
} else if (ht === "none") {
tile = tileArray[7];
}
} else if (equallen([ct, ft, it], "O") === 2 && equallen([ct, ft, it], "X") === 0) {
if (ct === "none") {
tile = tileArray[2];
} else if (ft === "none") {
tile = tileArray[5];
} else if (it === "none") {
tile = tileArray[8];
}
} else if (equallen([at, et, it], "O") === 2 && equallen([at, et, it], "X") === 0) {
if (at === "none") {
tile = tileArray[0];
} else if (et === "none") {
tile = tileArray[4];
} else if (it === "none") {
tile = tileArray[8];
}
} else if (equallen([ct, et, gt], "O") === 2 && equallen([ct, et, gt], "X") === 0) {
if (ct === "none") {
tile = tileArray[2];
} else if (et === "none") {
tile = tileArray[4];
} else if (gt === "none") {
tile = tileArray[6];
}
}
}
 
//Stops player from winning if possible
if (equallen(all, "X") >= 2 && tile === 0) {
if (equallen([at, bt, ct], "X") === 2 && equallen([at, bt, ct], "O") === 0) {
if (at === "none") {
tile = tileArray[0];
} else if (bt === "none") {
tile = tileArray[1];
} else if (ct === "none") {
tile = tileArray[2];
}
} else if (equallen([dt, et, ft], "X") === 2 && equallen([dt, et, ft], "O") === 0) {
if (dt === "none") {
tile = tileArray[3];
} else if (et === "none") {
tile = tileArray[4];
} else if (ft === "none") {
tile = tileArray[5];
}
} else if (equallen([gt, ht, it], "X") === 2 && equallen([gt, ht, it], "O") === 0) {
if (gt === "none") {
tile = tileArray[6];
} else if (ht === "none") {
tile = tileArray[7];
} else if (it === "none") {
tile = tileArray[8];
}
} else if (equallen([at, dt, gt], "X") === 2 && equallen([at, dt, gt], "O") === 0) {
if (at === "none") {
tile = tileArray[0];
} else if (dt === "none") {
tile = tileArray[3];
} else if (gt === "none") {
tile = tileArray[6];
}
} else if (equallen([bt, et, ht], "X") === 2 && equallen([bt, et, ht], "O") === 0) {
if (bt === "none") {
tile = tileArray[1];
} else if (et === "none") {
tile = tileArray[4];
} else if (ht === "none") {
tile = tileArray[7];
}
} else if (equallen([ct, ft, it], "X") === 2 && equallen([ct, ft, it], "O") === 0) {
if (ct === "none") {
tile = tileArray[2];
} else if (ft === "none") {
tile = tileArray[5];
} else if (it === "none") {
tile = tileArray[8];
}
} else if (equallen([at, et, it], "X") === 2 && equallen([at, et, it], "O") === 0) {
if (at === "none") {
tile = tileArray[0];
} else if (et === "none") {
tile = tileArray[4];
} else if (it === "none") {
tile = tileArray[8];
}
} else if (equallen([ct, et, gt], "X") === 2 && equallen([ct, et, gt], "O") === 0) {
if (ct === "none") {
tile = tileArray[2];
} else if (et === "none") {
tile = tileArray[4];
} else if (gt === "none") {
tile = tileArray[6];
}
}
}
 
//Other options in case the above are not fulfilled
//Controls the course of play over the game
if (tile === 0) {
switch (9 - available.length) {
case 1:
//If the center is taken, it plays randomly in the corner
//Otherwise, it takes the center
if (et === "X") {
tile = tileArray[choice([0, 2, 6, 8])];
} else {
tile = tileArray[4];
}
break;
 
case 3:
if (et === "X" && (equalanyof([at, ct, gt, it], "O"))) {
/*To counter the strategy of
O - -
- X -
X - -
 
O - -
- X -
- - X
and related strategies*/

if (at === "X") {
if (it === "none") {
tile = tileArray[8];
} else {
tile = tileArray[choice([2, 6])];
}
} else if (ct === "X") {
if (gt === "none") {
tile = tileArray[6];
} else {
tile = tileArray[choice([0, 8])];
}
} else if (gt === "X") {
if (ct === "none") {
tile = tileArray[2];
} else {
tile = tileArray[choice([0, 8])];
}
} else if (it === "X") {
if (at === "none") {
tile = tileArray[0];
} else {
tile = tileArray