Write a 'C' program to animate a circle?

The program in ‘C’ Programming language to draw a circle on the screen and animate it is as follows:

#include <stdio.h>

#include <conio.h>

#include <graphics.h>

#include <dos.h>

#define RADIUS 50

#define DELAY 20

void main()

{

            int x=0, y=0, gdriver=DETECT, gmode=4;

            clrscr();

            initgraph(&gdriver, &gmode, "C:\\TC\\BGI");

            while(!kbhit())

            {

                        for(x=0, y=0; x<getmaxy() && !kbhit();)

                        {

                                    circle(x++, y++, RADIUS);

                                    delay(DELAY);

                                    cleardevice();

                        }

                        cleardevice();

            }

            getch();

            closegraph();

}