tictactoegame.c

#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <math.h>
#include <ctype.h>
#include <stdlib.h>
#include <time.h>
#include <ctype.h>
#include <errno.h>

void resetBoard(){
    for(int i = 0; i<3; i++){
        for(int j = 0; j<3; j++){
            board[i][j] = ' ';
        }       
    }
}

void printBoard(){
    printf(" %c | %c | %c ",board[0][0],board[0][1],board[0][2]);
    printf("\n---|---|---\n");
    printf(" %c | %c | %c ",board[1][0],board[1][1],board[1][2]);
    printf("\n---|---|---\n");
    printf(" %c | %c | %c ",board[2][0],board[2][1],board[2][2]);
    printf("\n---|---|---\n");
    printf("\n");
}

int checkFreeSpaces(){
    int freeSpaces = 9;
    for(int i=0; i<3; i++){
        for(int j=0; j<3; j++){
            if(board[i][j]!=' '){
                freeSpaces--;
            }
        }    
    }
    return freeSpaces;
}

void playerMove(){
    int x;
    int y;
    do
    {
        printf("Enter row #(1-3): ");
        scanf("%d",&x);
        x--;
        printf("Enter column #(1-3): ");
        scanf("%d",&y);
        y--;
        if(board[x][y]!=' '){
            printf("Invalid move!\n");
        } else {
            board[x][y] = PLAYER;
            break;
        }
    } while (board[x][y]!=' ');
    

}

void computerMove(){
    // creates a seed based on current time
    srand(time(0));
    int x;
    int y;
    if(checkFreeSpaces()>0){
        do{
            x = rand() % 3;
            y = rand() % 3;
        } while(board[x][y]!=' ');
        board[x][y] = COMPUTER;
    } else {
        printWinner(' ');
    }
}

char checkWinner(){
    // check rows
    for(int i=0; i<3; i++){
        if(board[i][0]==board[i][1] && board[i][0]==board[i][2]){
            return board[i][0];
        }
    }
    // check columns
    for(int i=0; i<3; i++){
        if(board[0][i]==board[1][i] && board[0][i]==board[2][i]){
            return board[0][i];
        }
    }
    // check diagonals
    if(board[0][0]==board[1][1] && board[0][0]==board[2][2]){
        return board[0][0];
    }
    if(board[0][2]==board[1][1] && board[0][2]==board[2][0]){
        return board[0][2];
    }
    return ' ';
}

void printWinner(char winner){
    if(winner == PLAYER){
        printf("YOU WIN!");
    } else if(winner == COMPUTER){
        printf("YOU LOSE!");
    } else {
        printf("IT'S A TIE!");
    }
}

int main() {
    // TIC TAC TOE game
    char winner = ' ';
    char response;
    do{
        winner = ' ';
        response = ' ';
        resetBoard();
        while(winner==' ' && checkFreeSpaces()!=0){
            printBoard();
            playerMove();
            winner = checkWinner();
            if(winner!=' ' || checkFreeSpaces()==0){
                break;
            }
            computerMove();
            winner = checkWinner();
            if(winner!=' ' || checkFreeSpaces()==0){
                break;
            }
        }
        printBoard();
        printWinner(winner);
        printf("\nWould you like to play again? (Y/N): ");
        scanf(" %c");
        scanf("%c",&response);
        response = toupper(response);
    }while(response=='Y');
    printf("Thanks for playing!");
    
    return 0;
}

// Bro Code. (2021.10.7.). C Programming Full Course for free [Video]. YouTube. https://www.youtube.com/watch?v=87SH2Cn0s9A