#include<bits/stdc++.h>

using namespace std;

const int N = 110;

typedef long long ll;

int n;
ll a[N];

int main()
{
    scanf("%d",&n);
    for(int i = 1;i <= n;i ++ ) scanf("%lld",&a[i]);
    ll sum = 0;
    for(int i = 1;i <= n;i ++ ) sum |= a[i];
    int x = 0;
    for(x = 0; ; x ++)
    {
        if((sum & 1) == 0) break;
        sum >>= 1;
    }
    ll ans = 1ll << x;
    printf("%lld\n",ans);
    return 0;
}