#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <graphics.h>
void main() {
int    GraphDriver;             /* The Graphics device driver           */
int    GraphMode;               /* The Graphics mode value              */
struct point { int x,y; } p1,pp[40];
int radius,i,n;
float d;

  printf("give me the center--->"); scanf("%d %d",&p1.x,&p1.y);
  printf("give me the radius -->"); scanf("%d",&radius);
  printf("give me the max polygon-->"); scanf("%d",&n);

  if (n < 3)  exit(1);  getche();

  GraphDriver = DETECT;                 /* Request auto-detection       */
  initgraph( &GraphDriver, &GraphMode, "" ); /* just increasing p1 - p2 */
  d=2*3.14159/n; setcolor(6);
  for (i=0; i<=n; i++) {
    pp[i].x=p1.x+radius*cos(d*i); pp[i].y=p1.y+radius*sin(d*i);
  }
  drawpoly(n+1,(int *)pp);

  getche(); closegraph();   /* Return the system to text mode       */
}