简单的贪吃蛇程序。备有详细的备注。程序比较简单，非常易懂，适合于初学C语言的同学们参考。可以完成贪吃蛇的基本功能，设置障碍物，速度的控制-Snake simple procedure. With detailed notes. Procedure is relatively simple, very easy to understand, suitable for novice C language reference classmates. Snake can complete basic f