#include <iostream>
#include <string>
#include <cstdio>
#include <algorithm>
using namespace std;
int main()
{
    int x1,x2,y1,y2;
    scanf("%d%d",&x1,&y1);
    scanf("%d%d",&x2,&y2);
    if(x1==x2 || y1==y2)
    {
        printf("2");
        }
    if(x1!=x2 && y1!=y2)
    {
        printf("1");
        }
    return 0;
}