#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll = long long;
#define all(x) (x).begin(), (x).end()
template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
    os << p.first << ' ' << p.second;
    return os;
}
template <typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &p) {
    is >> p.first >> p.second;
    return is;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v) {
    ll s = (ll)v.size();
    for (ll i = 0; i < s; i++) os << (i ? ' ' : ' ') << v[i];
    return os;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &v) {
    for (auto &x : v) is >> x;
    return is;
}
//エラトステネスのふるい
bool IsPrime(ll num)
{
    if (num < 2) return false;
    else if (num == 2) return true;
    else if (num % 2 == 0) return false; // 偶数はあらかじめ除く

    double sqrtNum = sqrt(num);
    for (int i = 3; i <= sqrtNum; i += 2)
    {
        if (num % i == 0)
        {
            // 素数ではない
            return false;
        }
    }

    // 素数である
    return true;
}
#define rep(i, n) for (ll (i) = 0; (i) < (ll)(n); (i)++)
int main() {
    ll a,b,o,ab;
    cin >> a >> b >> o >> ab;
    cout << o+max(a,b)+ab << endl;
}