#include<graphics.h>
#include<iostream.h>
#include<stdlib.h>
#include<conio.h>

#include<dos.h>
#include<math.h>

void Polygon(int xc, int yc, int r, int Side);
void Lineto(int, int, int=0);
void Line(int, int, int, int);
void DDALine(int, int, int, int);
void Circle(int, int, int);
void PlotPoints(int, int, int, int);
void Ellipse(int, int, int, int);

char far *Scr;

void SetPixel(unsigned x, unsigned y, unsigned color)
{
	char col;
	 col = Scr[(y << 8) + (y << 6) + ( x / 2 )] ;
	if(x/2)
	{
	   asm mov al,col;
	   asm mov cl,4;
	   asm shl al,cl;
	   asm add al,byte ptr color;
	   asm rol al,cl;
	   asm mov col,al;
	}
	else
	{
	   asm mov al,col;
	   asm and al,0xf0;
	   asm add al,byte ptr color;
	   asm mov col,al;
	}
   Scr[(y << 8) + (y << 6) + (x / 2)] = col;

}

template <class T>
T abs(T x)
{
	if(x < 0)
		return (-1 * x);
	else
		return x;
};
unsigned Round(float x)
{
	return ((x * 10 + 5) / 10);
}

void main()
{
/*	asm mov ah, 0x0;
	asm mov al, 0x13;
	asm int 0x10;      */

/*	int gdriver = DETECT, gmode, errorcode;
	initgraph(&gdriver, &gmode, "c:\\la\\tc\\bgi");
  */
//	Scr = (char far *)0xA0000000;


//	Line(1,1,8,5);
	clrscr();
	cout<<endl;
	Circle(3, 2, 3);
	getch();
	getch();
//	closegraph();

}

void Circle(int xc, int yc, int r)
{
	int x = 0, y = r, p;
	p = 1 - r;
//	PlotPoints(xc, yc, x, y);
	cout<<x<<"\t"<<y<<"\t"<<p<<endl;
	for(; x < y;)
	{
		x++;
		if(p < 0)
			p = p + 2 * x +1;
		else
		{
			y = y - 1;
			p = p +  2 * (x - y) + 1;
		}
//		delay(50);
//		PlotPoints(xc, yc, x, y);
		cout<<x<<"\t"<<y<<"\t"<<p<<endl;

	}

}
void PlotPoints(int xc, int yc, int x, int y)
{
	putpixel(xc + x, yc + y, 1);
	putpixel(xc - x, yc + y, 2);
	putpixel(xc + x, yc - y, 3);
	putpixel(xc - x, yc - y, 4);
	putpixel(xc + y, yc + x, 5);
	putpixel(xc - y, yc + x, 6);
	putpixel(xc + y, yc - x, 7);
	putpixel(xc - y, yc - x, 8);
}