#include <bits/stdc++.h>
using namespace std;
#define ll long long 
const ll INF = 1e18;

//
#define TIME (1.0* clock()/CLOCKS_PER_SEC)
#define file(name) if(fopen(name".inp","r")){freopen(name".inp","r",stdin); freopen(name".out","w",stdout);}
#define hackspeed ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr)
//


int main(){
	hackspeed;
	//file("");
	ll m,n,p,q; cin >> m >> n >> p >> q;
	ll s=-1;
	if((p==1 || p==m)&&(q==1||n==q)) cout << 3;
	else if((p==1 || p==m)||(q==1||n==q)) cout <<5;
	else cout << 8;




	//time
	cerr << "Time elapsed: " << TIME << "s.\n";
	return 0;
}