用MVC框架编写的贪食蛇小游戏代码，使用方向键操控一条长长的蛇不断吞下豆子，同时蛇身随着吞下的豆子不断变长，当蛇头撞到蛇身或障壁时游戏结束-MVC fr a mework written with Snake game code, use the arrow keys to control a long snake beans continue to swallow, but swallow the snake beans with continuous variable length, whe