#include <bits/stdc++.h>

using ll = long long;

using namespace std;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n;
    cin >> n;
    cin.ignore();

    vector<ll> v(n);

    for (int i = 0; i < n; ++i)
    {
        string s;
        getline(cin, s);

        if (s.find(" ")!=string::npos)
        {
            cout << "\"assert\"\n";

            return 0;
        }

        v[i] = stoll(s);
    }

    sort(v.rbegin(), v.rend());
    vector<ll> v0;
    v0.push_back(v[0] + v[1]);
    v0.push_back(v[0] + v[2]);
    v0.push_back(v[1] + v[2]);

    decltype(v0)::iterator result = unique(v0.begin(), v0.end());
    v0.erase(result, v0.end());

    sort(v0.rbegin(), v0.rend());
    ll res = v0[1];

    printf("%lld\n", res);

    return 0;
}