Bresenhams Circle Drawing Algorithm Implementation in C

Bresenham's circle drawing algorithm is one of the basic algorithms in computer graphics. Bresenham's circle drawing algorithm helps to draw circles with minimal calculations. Here is a simple c program that implements Bresenham's circle drawing algorithm.

The program is as follows:

#include<stdio.h>
#include<graphics.h>

void bres(int xc,int yc,int r)
{
int p,k,x,y;
p=1-r;
x=0;
y=r;
for(k=0;k<=y;k++)
{
putpixel(xc+x,yc+y,5);
putpixel(xc-y,yc-x,5);
putpixel(xc+y,yc-x,5);
putpixel(xc-y,yc+x,5);
putpixel(xc+y,yc+x,5);
putpixel(xc-x,yc-y,5);
putpixel(xc+x,yc-y,5);
putpixel(xc-x,yc+y,5);
if(p>0)
 {
 p=p+2*(x+1)+1-2*(y+1);
 x++;
 y--;
 }
else
 {
 p=p+2*(x+1)+1;
 x++;
 }
}
}


int main()
{
int gd=DETECT,gm;
int xc,yc,r;
printf("Enter the center and radius");
scanf("%d%d%d",&xc,&yc,&r);
initgraph(&gd,&gm,"..\\BGI\\");
bres(xc,yc,r);
delay(1500);
getch();
return 0;
}