根据输入的半径长度和原点坐标画出圆，圆周用点表示-According to input the length and the radius of the origin coordinates to draw circle, circle with point

这是在屏幕上画坐标的例程，首先要知道的一点就是，屏幕坐标和我们平常的坐标是不一样的，我们一般理解的是屏幕左下角是坐标原点，而实际上屏幕坐标原点在左上角，X轴向右增加，Y轴向下增加-This is painted on the screen coordinates of the routine, the first thing to know is that the screen coordinates and the coordinates of our usual is not the sam