#include<cstdio>
#include<bitset>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rrep(i, n) for (int i = (int)(n)-1; i >= 0; i--)
#define rep2(i, a, b) for (int i = (int)a; i < (int)(b); i++)
#define rrep2(i, a, b) for (int i = (int)(b)-1; i >= (int)(a); i--)
bitset<65536> dp[2];
int main(){
    int N;
    scanf("%d", &N);
    if(N >= 16) printf("65535\n");
    else{
        dp[0].flip(0);
        rep(i, N){
            int A;
            scanf("%d", &A);
            dp[(i&1)^1] = 0;
            rep(j, 16){
                rep(k, 65535) if(dp[i&1][k]) dp[(i&1)^1].set(k | A);
                A = (A>>1) | ((A&1)<<15);
            }
        }
        int now = 65535;
        while(true){
            if(dp[N&1][now]){
                printf("%d\n", now);
                return 0;
            }
            now--;
        }
    }
}