#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
	ll a, b, o, w;
	cin >> a >> b >> o >> w;
	if(o > 0) {
		cout << o + max(a, b) + w;
	} else if(a > b) {
		cout << a + w;
	} else {
		cout << b + w;
	}
	return 0;
}