Bresenhams Circle Algorithm

// C-program for circle drawing 
// using Bresenham’s Algorithm 
// in computer-graphics 
#include <stdio.h> 
#include <dos.h> 
#include <graphics.h> 

// Function to put pixels 
// at subsequence points 
void drawCircle(int xc, int yc, int x, int y) 
{ 
	putpixel(xc+x, yc+y, RED); 
	putpixel(xc-x, yc+y, RED); 
	putpixel(xc+x, yc-y, RED); 
	putpixel(xc-x, yc-y, RED); 
	putpixel(xc+y, yc+x, RED); 
	putpixel(xc-y, yc+x, RED); 
	putpixel(xc+y, yc-x, RED); 
	putpixel(xc-y, yc-x, RED); 
} 

// Function for circle-generation 
// using Bresenham's algorithm 
void circleBres(int xc, int yc, int r) 
{ 
	int x = 0, y = r; 
	int d = 3 - 2 * r; 
	drawCircle(xc, yc, x, y); 
	while (y >= x) 
	{ 
		// for each pixel we will 
		// draw all eight pixels 
		
		x++; 

		// check for decision parameter 
		// and correspondingly 
		// update d, x, y 
		if (d > 0) 
		{ 
			y--; 
			d = d + 4 * (x - y) + 10; 
		} 
		else
			d = d + 4 * x + 6; 
		drawCircle(xc, yc, x, y); 
		delay(50); 
	} 
} 

// Your code needs a driver function 	
int main() 	
{ 	
	int cir = 50, cor = 50, r2 = 30; 	
	int gd = DETECT, gm; 	
	initgraph(&gd, &gm, ""); // initializing the library graph 	
	circleBres(cir, cor, r2); // function call under execution 	
	return 0; 	
}