说明：  tc3下俄罗斯方块程序 采取定义boland图形库（<graphics.h>），需编译前将turboc目录下的egavga.bgi考到源程序所在目录下
(TC3 under procedures adopted Tetris Boland definition graphics library (lt; Graphics.hgt;) , Will be compiled before the TurboC directory egavga.bgi test to the directory containing the source)