Tic Tac Toe – C

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>

char square[10] = { ‘0’, ‘1’, ‘2’, ‘3’, ‘4’, ‘5’, ‘6’, ‘7’, ‘8’, ‘9’ };
int choice, player;

int checkForWin();
void displayBoard();
void markBoard(char mark);

int main()
{
int gameStatus;
char mark;
int draw;
int win;

player = 1;

do
{
displayBoard();
//change turn
player = (player % 2) ? 1 : 2;

//get input
printf(“Player %d, Enter a number: “, player );
scanf(“%d”, &choice);

//get the correct character based on the player turn
mark = (player == 1) ? ‘X’ : ‘O’;

//set board based on user choice or invaild choice
markBoard(mark);

gameStatus = checkForWin();

player++;

}while(gameStatus == -1);

if (gameStatus == 1)
printf(“==>\aPlayer %d win”, — win);

else
printf(“==>\aGame”, draw);

return 0;
}
/******************************************
FUNCTION TO RETURN TO GAME STATUS
1 FOR THE GAME IS OVER WITH THE RESULT
-1 FOR THE GAME IS IN PROCESS
0 GAME IS OVER AND NO RESULT
******************************************/
int checkForWin()
{
int returnValue = 0;
if ( square[1] == square[2] && square[2] == square[3])
returnValue = 1;

else if ( square[4] == square[5] && square[5] == square[6])
returnValue = 1;
else if ( square[7] == square[8] && square[8] == square[9])
returnValue = 1;
else if ( square[1] == square[4] && square[4] == square[7])
returnValue = 1;

else if ( square[2] == square[5] && square[5] == square[8])
returnValue = 1;

else if ( square[4] == square[5] && square[4] == square[5])
returnValue = 1;

else if ( square[3] == square[6] && square[6] == square[9])
returnValue = 1;

else if ( square[1] == square[5] && square[5] == square[9])
return 1;

else if ( square[3] == square[5] && square[5] == square[7])
returnValue = 1;

else if ( square[1]!= ‘1’ && square[2]!= ‘2’ && square[3]!= ‘3’ && square[4]!= ‘4’ && square[5]!= ‘5’ && square[6]!= ‘6’ && square[7]!= ‘7’ && square[8]!= ‘8’ && square[9]!= ‘9’)
returnValue = 0;

else
returnValue = -1;

return returnValue;
}

/****************************************************************
FUNCTION TO DRAW TIC TAC TOE WITH PLAYERS MARK
****************************************************************/

void displayBoard()
{
system(“cls”);
printf(“\n\n\tTic Tac Toe\n\n”);

printf(“Player 1 (X) – Player 2 (O)\n\n\n”);

printf(” | | \n “);
printf(“%c | %c | %c\n”, square[1], square[2], square[3]);

printf(” |______ |__________ \n”);
printf(” | | \n”);

printf(“%c | %c | %c\n”, square[4], square[5], square[6]);

printf(” |______ |__________ \n”);
printf(” | | \n”);

printf(“%c | %c | %c\n”, square[7], square[8], square[9]);

printf(” | | n\n”);

}

/*****************************************************************
set the board with the correct character,
x or o in the correct spot in the array
*****************************************************************/
void markBoard(char mark)
{
if (choice == 1 && square[1] == ‘1’)
square[1] = mark;

else if (choice == 2 && square[2] == ‘2’)
square[2] = mark;

else if (choice == 3 && square[3] == ‘3’)
square[3] = mark;

else if (choice == 4 && square[4] == ‘4’)
square[4] = mark;

else if (choice == 5 && square[5] == ‘5’)
square[5] = mark;

else if (choice == 6 && square[6] == ‘6’)
square[6] = mark;

else if (choice == 7 && square[7] == ‘7’)
square[7] = mark;

else if (choice == 8 && square[8] == ‘8’)
square[8] = mark;

else if (choice == 9 && square[9] == ‘9’)
square[9] = mark;

else
{
printf(“Invalid move”);
player–;
getch();

}
}