Tic Tac Toe 是兩個玩家交替放置 Xs 和 Os 的遊戲
Tic-tac-toe also known as noughts and crosses, or also Xs and Os is a paper-and-pencil game for two players who take turns marking the spaces in a three-by-three grid with X or O. The player who succeeds in placing three of their marks in a horizontal, vertical, or diagonal row is the winner. It is a solved game, with a forced draw assuming best play from both players.