#include <iostream>
#include <vector>
using namespace std;
typedef long long ll;

signed main() {
    ll n;
    std::cin >> n;
    vector<ll> nums(n);
    for(ll i = 0; i < n; i++) std::cin >> nums[i];

    vector<ll> counts(65);

    ll out = 0;
    ll curr = 0;
    for(ll i = 0; i < 64; i++) {
        for(ll j = 0; j < n; j++) {
            if((1LL << i) & nums[j]) curr++;
        }
        if(curr) out |= (1LL << i);
        curr /= 2LL;
    }

    std::cout << out << endl;
}