tictactoe.c

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

char b[9] = {' ',' ',' ',' ',' ',' ',' ',' ',' '};
int gameStatus;
int boardSquare;
int turn;
int turnNumber;

/*checks the status of the game and sets gameStatus accordingly (1=winner/gameover, 0=game ongoing)*/
void
status()
{
    if((b[0]!=' ' && b[1]!=' ' && b[2]!=' '&& b[0]==b[1] && b[1]==b[2]),
       (b[3]!=' ' && b[4]!=' ' && b[5]!=' '&& b[3]==b[4] && b[4]==b[5]),
       (b[6]!=' ' && b[7]!=' ' && b[8]!=' '&& b[6]==b[7] && b[7]==b[8]),
       (b[0]!=' ' && b[3]!=' ' && b[6]!=' '&& b[0]==b[3] && b[3]==b[6]),
       (b[1]!=' ' && b[4]!=' ' && b[7]!=' '&& b[1]==b[4] && b[4]==b[7]),
       (b[2]!=' ' && b[5]!=' ' && b[8]!=' '&& b[2]==b[5] && b[5]==b[8]),
       (b[0]!=' ' && b[4]!=' ' && b[8]!=' '&& b[0]==b[4] && b[4]==b[8]),
       (b[2]!=' ' && b[4]!=' ' && b[6]!=' '&& b[2]==b[4] && b[4]==b[6])) {
        gameStatus++;
    }
}

/*clears the screen and prints the board.*/
void
board()
{
    system("clear");
    printf(" %c | %c | %c \n-----------\n %c | %c | %c \n-----------\n %c | %c | %c \n",\
        b[0],b[1],b[2],b[3],b[4],b[5],b[6],b[7],b[8]);
    printf("\ngameStatus: %i\n", gameStatus);
    printf("boardSquare: %i\n", boardSquare);
    printf("turn: %i\n", turn);
    printf("turnNumber: %i\n", turnNumber);
}

/*takes an input from the player, checks who's turn it is,
 * and sets the corresponding square to the letter of who's turn it is*/
void
boardInput()
{
    printf("\nSelect square: ");
    scanf("%i", &boardSquare);
    if(turn==0) {
        if(b[boardSquare]==' ') {
            b[boardSquare]='X';
        }
    } else {
        if(b[boardSquare]==' ') {
            b[boardSquare]='O';
        }
    }
}

/*Progresses the counter of turns and changes who's turn it is */
void
nextTurn()
{
    if(b[boardSquare]=='X'){
        turn=1;
        turnNumber++;
    } else {
        turn=0;
        turnNumber++;
    }
}

int
main(void)
{
    while(1) {
        status();
        if(gameStatus==0 && turnNumber==8) {
            system("clear");
            printf("Tie!\n");
            break;
        }
        if(gameStatus==1) {
            system("clear");
            printf("Player wins!");
            break;
        }
        board();
        boardInput();
        nextTurn();
    }
}