功能： 实现简易贪吃蛇游戏软件

基本要求：在封闭的围墙内有一条蛇，通过键盘控制蛇的运动方向，若无按键时，按蛇头方向自行移动。围墙内随机出现食物，吃掉食物，蛇的身体长1节，得10分。若蛇在移动过程中，撞到墙壁或身体交叉蛇头撞到自己的身体游戏结束。注意蛇只能以蛇头移动，不能相反，也就是说，若蛇原先向上移动，按向下键无效。-Features: Simple Snake game software to achieve the basic requirements: in a closed within the walls of a snake, a snake through the keyboard to control the direction of movement, without keys, press the smugglers moving their own direction. The walls were a food, eat food, the snake' s body length of 1, 10 points. If the snake on the move, hit the wall or physical cross-smugglers hit game over his body. Note that the snake can only smugglers moving, not the opposite, that is, if the original snake moving up, press the down key is invalid.