Please help me for making bouncing ball in turbo c

#include <graphic.h>
#include <Dos.h>
#include <canio.h>
Int main()
{
Int gd= detect,gm;
Int x,yx,ix,iy;
X=0;
Y=0;
Initgraph(&gd,&gm, "c:\\TC\\BGI");
While(!kbhit())
{
Circle(x,y,10);
x=x+ix;
y=y+iy;
if(y>=get maxy())
iy=iy*-1;
delay(200);
cleardevice();
}
Getch();

This will work in 2 direction down and right i need it in for direction what will i do