//
// Created by cteam12 on 10/24/26.
//

#include <iostream>
#include <vector>

using namespace std;

typedef unsigned long long ull;

int main() {
    int x;
    cin >> x;

    vector<ull> y;
    for (int i = 0; i < x; i++) {
        ull c;
        cin >> c;
        y.push_back(c);
    }

    for (int i = 0; i < x; i++) {
        ull ssum = 0;
        for (int j = i; j < x; j++) {
            ssum += y[j];
        }
        y.push_back(ssum);
    }

    ull bin = 0;

    for (ull bit : y) {
        bin |= bit;
    }

    cout << bin << '\n';

    return 0;
}