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

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

    ll n;
    cin >> n;
    vi a(n);
    ll sum = 0;

    for (ll& x : a) {
        cin >> x;
        sum += x;
    }

    for (ll& x : a) {
        sum |= x;
    }

    cout << sum << '\n';

    return 0;
}