说明：  程序实现根据鼠标输入的点进行Bezier曲线的绘制，程序中鼠标 *输入点的个数是可以手动改动的，此程序中输入点的最大值设置为. *同时，程序实现了键盘的交互，用来控制程序运行过程中的退出、重画等
(Bezier curve drawing program point the mouse input, mouse* the number of input points in the program can be manually changed, the maximum is set to input point in this program.* At the same time, the program has achieved keyboard interaction with to control the exit in the program is running, redraw)