#include <iostream>

using namespace std;

int x1,x2,y1,y2;

int main(){

    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    cin>>x1>>y1>>x2>>y2;
    if(x1==x2 || y1==y2)cout<<2;
    else cout<<1;


}