实现贪吃蛇，游戏中，两名玩家分别控制一个角色在屏幕上移动，所经之处砌起围栏。角色只能向左、右方向90度转弯，游戏目标保证让对方先撞上屏幕或围栏。-Achieve Snake, the game, two players each control a character on the screen moves, the ascent of the fence by the Department. Role can only be to the left and right direction of 90 degree turn, the game first hit the target to ensure that the other side screen or fence.