Thread: tic tac toe

To test my C++ skills, i tried making a tic tac toe game. There is an error though. Occasionally it will put the X in the wrong spot, or it will put 2 letters on the board. Can you please tell me why itll put 2 letters on or why it doesnt put it in the right spot? Thanks!!!

Code:

#include <iostream>
using namespace std;

class board {
 char board[2][2];

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

  void display() {
   cout << "     X     \n";
   cout << " 0 | 1 | 2\n\n";
   for(int i = 0; i < 3; i++) {
    cout << " " << board[i][0] << " | " << board[i][1] << " | " << board[i][2] << " ";
    cout << "  " << i;
    if(i == 1) {
     cout << " Y ";
    }
    if(i != 2) {
     cout << "\n---|---|---  -\n";
    }
   }
  }

  void playerMove() {
   int x, y;
   cout << "\nEnter x coordinate: ";
   cin >> x;
   cout << "\nEnter y coordinate: ";
   cin >> y;
   if(board[x][y] != ' ') {
    cout << "Incorrect coordinate. Please enter again.\n";
    playerMove();
   } else {
    board[x][y] = 'X';
   }
  }

  void computerMove() {
   if((board[0][0] == board[1][1]) && (board[2][2] == ' ')) {
    board[2][2] = 'O';
    return;
   }
   if((board[1][1] == board[2][2]) && (board[0][0] == ' ')) {
    board[0][0] = 'O';
    return;
   }
   if((board[0][0] == board[2][2]) && (board[1][1] == ' ')) {
    board[1][1] = 'O';
    return;
   }
   if((board[0][2] == board[1][1]) && (board[2][0] == ' ')) {
     board[2][0] = 'O';
     return;
   }
   if((board[2][0] == board[1][1]) && (board[0][2] == ' ')) {
    board[0][2] = 'O';
    return;
   }
   if((board[2][0] == board[0][2]) && (board[1][1] == ' ')) {
    board[1][1] = 'O';
    return;
   }
   for(int i = 0; i < 3; i++) {
    for(int j = 0; j < 3; j++) {
     if(board[i][j] == ' ') {
      board[i][j] = 'O';
      return;
     }
    }
   }
  }

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

int main() {
 board b;
 char win;
 do {
  b.display();
  b.playerMove();
  win = b.checkWinner();
  if(win != ' ') {
   break;
  }
  b.computerMove();
  win = b.checkWinner();
 } while(win == ' ');
 if(win == 'X') {
  cout << "\nYOU WIN!\n\n";
 } else {
  cout << "\nTHE COMPUTER WINS!\n\n";
 }
 b.display();
 return 0;
}

a little late, arent we? :P

Woo hoo! Thank you guys !