利用mfc开发的一个XO游戏，即五子棋的简化版（也可以成为三子棋）。算法简单，程序也简单，适合一些初学mfc的人学习一下。-XO using mfc development of a game, that is a simplified version of backgammon (you can also become the third son of chess.) Algorithm is simple, the program is also simple, suitable for t