Mid Point circle Drawing Algorithm

#include<stdio.h>
#include<conio.h>
#include<graphics.h>
#include<dos.h>
#include<math.h>

void main(){
 int gd=DETECT, gm;
 int xc,yc,r,p,x,y;
 initgraph(&gd,&gm,"C:\\TURBOC3\\BGI");
 x=0;
 printf("Enter radius : \n");
 scanf("%d",&r);
 y=r;
 printf("Enter x center and y center : \n");
 scanf("%d%d",&xc,&yc);

 drawcircle(xc,yc,x,y);
 p=1-r;
 while(x<y){
  if(p<0){
   x++;
  }
  else{
   x++;
   y--;
  }
  if(p<0)
   p=p+2*x+1;
   else
   p=p+2*(x-y)+1;

   drawcircle(xc,yc,x,y);

 }

 getch();
}


int drawcircle(int xc, int yc, int x, int y){
 putpixel(xc+x,yc+y,1);
 putpixel(xc+y,yc+x,1);
 putpixel(xc-y,yc+x,1);
 putpixel(xc-x,yc+y,1);
 putpixel(xc-x,yc-y,1);
 putpixel(xc-y,yc-x,1);
 putpixel(xc+y,yc-x,1);
 putpixel(xc+x,yc-y,1);

 return 0;
}