#include <bits/stdc++.h>
using namespace std;
int main()
{
    long long x1, y1, x2, y2;
    scanf("%ld %ld %ld %ld", &x1, &y1, &x2, &y2);
    if(x1==x2 || y1==y2)
    printf("2");
    else
    printf("1");

    return 0;
}