#include <iostream>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#include <iomanip>
#include <queue>
#include <algorithm>
#include <numeric>
#include <deque>
#include <complex>
#include <cassert>

using namespace std;
using ll = long long;

int main(){

    int N, A, mx=1<<16, ans=0;
    cin >> N;
    if (N >= 16){
        cout << mx-1 << endl;
    }

    deque<bool> dp(mx);
    dp[0] = 1;
    for (int i=0; i<N; i++){
        cin >> A;
        deque<bool> pd(mx);
        for (int j=0; j<16; j++){
            A = A/2 + (1<<15) * (A % 2);
            for (int j=0; j<mx; j++){
                pd[j|A] |= dp[j];
            }
        }
        swap(dp, pd);
    }

    for (int i=0; i<mx; i++) if (dp[i]) ans=i;

    cout << ans << endl;

    return 0;
}