#include <algorithm>
#include <array>
#include <cmath>
#include <cstdio>
#include <deque>
#include <iomanip>
#include <iostream>
#include <numeric>
#include <optional>
#include <queue>
#include <set>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;

int main() {
    string n, s;
    getline(cin, n);
    getline(cin, s);
    if (s.find(' ') != string::npos) {
        cout << "assert" << endl;
        return 0;
    }
    int64_t a0 = stoll(s);
    int64_t a1, a2;
    cin >> a1 >> a2;
    vector<int64_t> ss = {a0 + a1, a0 + a2, a1 + a2};
    sort(ss.rbegin(), ss.rend());
    cout << (ss[0] == ss[1] ? ss[2] : ss[1]) << endl;
    return 0;
}