/*   @JUDGE_ID:   1705PZ   143   C */
#include <stdio.h>
#include <math.h>

int check(float x0,float y0,float x1,float y1,float gx,float gy,float x,float y)
{
	float m;
	if(x0 == x1){
		if((gx - x0) * (x - x0) >= 0)
			return 1;
		return 0;
	}
	m = (y1 - y0) / (x1 - x0);
	if((m * (x - x0) + (y0 - y)) * (m * (gx - x0) + (y0 -gy)) >= 0)
		return 1;
	return 0;
}

float max(float x1,float x2,float x3)
{
	if(x1 >= x2){
		if(x1 >= x3)
			return x1;
		return x3;
	}else{
		if(x2 >= x3)
			return x2;
		return x3;
	}
}

float min(float x1,float x2,float x3)
{
	if(x1 <= x2){
		if(x1 <= x3)
			return x1;
		return x3;
	}else{
		if(x2 <= x3)
			return x2;
		return x3;
	}
}

int main()
{
	int count;
	float i,j,gx,gy,maxx,maxy,minx,miny,x1,y1,x2,y2,x3,y3;
	while(1)
	{
		scanf("%f %f %f %f %f %f",&x1,&y1,&x2,&y2,&x3,&y3);
		if(x1 == 0 && x2 == 0 && x3 == 0 && y1 ==0 && y2==0 && y3==0)
			break;
		maxx = max(x1,x2,x3);maxy = max(y1,y2,y3);
		minx = min(x1,x2,x3);miny = min(y1,y2,y3);
		gx = (x1 + x2 + x3) / 3;gy = (y1 + y2 + y3) / 3;
		count = 0;
		for(i = floor(minx);i <= ceil(maxx);i += 1)
			for(j = floor(miny);j <= ceil(maxy);j += 1)
				if(check(x1,y1,x2,y2,gx,gy,i,j) && check(x1,y1,x3,y3,gx,gy,i,j) && check(x2,y2,x3,y3,gx,gy,i,j))
					count++;
		printf("%4d\n",count);
	}
	return 0;
}
@END_OF_SOURCE_CODE