#include <stdlib.h>
#include <math.h>
#include <conio.h>
#include <graphics.h>
void main()
{
  struct point { int x,y; } p1, pbe;
  int Drive, Mode,i, p, n;
  float inc, t, tx, ty, sc, x1, y1;

  printf("give me the circle point --> "); scanf("%d %d",&p1.x,&p1.y);
  printf("input the p --> "); scanf("%d",&p);
  Drive=DETECT; initgraph(&Drive, &Mode, ""); setcolor(14);
  line(0,p1.y,639,p1.y); line(p1.x,0,p1.x,479);

  for (i=0,t=-4; t<=4; t+=.5) {
    tx=2*p*t; ty=p*t*t;    /*   x=2*p*t    y=p*t*t   */
    x1=tx+p1.x; y1=p1.y-ty;   /* rx=x+p1.x     ry=p1.y-y   */
    if (i==0) { moveto(x1,y1); i=1; }
    else lineto(x1, y1);
    delay(2500);
  }
  getche(); closegraph();
}