#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
const int inf = INT_MAX / 2;
const ll infl = 1LL << 60;
#define rep(i,a,b) for(int i = a; i < b; ++i)
#define rrep(i,a,b) for(int i = a; i >= b; --i)
#define all(x) (x).begin(),(x).end()
template<class T>bool chmax(T& a, const T& b) { if (a < b) { a = b; return 1; } return 0; }
template<class T>bool chmin(T& a, const T& b) { if (b < a) { a = b; return 1; } return 0; }
const int MOD = 998244353;

int main(){
  int a, b, o, w;
  cin >> a >> b >> o >> w;
  int ans = 0;
  ans = max(a,b)+o+w;
  cout << ans << endl;

  return 0;
}