#include<bits/stdc++.h>
#define pt printf(">>>")
#define mid (((l)+(r))/2)
using namespace std;
typedef long long ll;
typedef long double ld;
const ll N=1e6+10,inf=1e18+10,mod=1e9+7;
const ll dir[4][2]={{1,0},{-1,0},{0,1},{0,-1}};
int main(){
	ll a,b,o,w;
	cin >> a >> b >> o >> w;
	cout << a+b+o+w-min(a,b);
	return 0;
}