UVa 11494 Queen Solution

#include<stdio.h>
int main()
{
int x1,y1,x2,y2,dx,dy;
while(scanf("%d %d %d %d",&x1,&y1,&x2,&y2)==4)
{
if(x1==0 && x2==0 && y1==0 && y2==0)
break;
if(x1>x2)
dx=x1-x2;
else
dx=x2-x1;
if(y1>y2)
dy=y1-y2;
else
dy=y2-y1;
if(dx==0 && dy==0)
printf("0\n");
else if(dx==dy || dx==0 || dy==0)
printf("1\n");
else
printf("2\n");
}
}