Tic Tac Toe

Rules of the game :
* The game is played on a grid that's 3 squares by 3 squares.
* Two players take turns putting their marks in empty squares with either X or O.
* The first player to get 3 of her marks in a row (up, down, across, or diagonally) is the winner.
* If all 9 squares are full and no player has 3 marks in a row, the game is a draw.