Bouncing Ball in C Programming

#include<conio.h>

#include<graphics.h>

#include<dos.h>

#include<math.h>

#include<stdlib.h>

void main()

{

int gd=DETECT,gm;

initgraph(&gd,&gm,"c:\\tc\\bgi");

int xinc=5,yinc=5,r=10;

while(!kbhit()!=0)

{

xinc=xinc+5;

yinc=yinc+5;

r++;

if(xinc>=630)

{

xinc=-xinc;

}

if(yinc>=470)

{

yinc=-yinc;

}

if(r==25)

{

r=-r;

}

setfillstyle(1,rand());

circle(abs(xinc),abs(yinc),abs(r));

floodfill(abs(xinc),abs(yinc),WHITE);

delay(10);

cleardevice();

}

getch();

closegraph();

}