#include "secret.h"
#include <bits/stdc++.h>
#define MAXN 1001
using namespace std;
int N;
int A[MAXN];
vector<int> pf[MAXN * 4], sf[MAXN * 4];
void build(int v = 0, int l = 0, int r = N - 1){
pf[v].resize(r - l + 1);
sf[v].resize(r - l + 1);
pf[v][0] = A[l];
for(int i = 1; i <= r - l; i++){
pf[v][i] = Secret(pf[v][i - 1], A[l + i]);
}
sf[v][r - l] = A[r];
for(int i = r - l - 1; i >= 0; i--){
sf[v][i] = Secret(A[l + i], sf[v][i + 1]);
}
if(l != r){
int m = (l + r) / 2;
build(v * 2 + 1, l, m);
build(v * 2 + 2, m + 1, r);
}
}
int qry(int l, int r, int v = 0, int tl = 0, int tr = N - 1){
int tm = (tl + tr) / 2;
if(l == r) return A[l];
if(l <= tm && tm < r){
return Secret(sf[v * 2 + 1][l - tl], pf[v * 2 + 2][r - (tm + 1)]);
}
if(r <= tm){
return qry(l, r, v * 2 + 1, tl, tm);
}else{
return qry(l, r, v * 2 + 2, tm + 1, tr);
}
}
void Init(int N, int A[]) {
::N = N;
for(int i = 0; i < N; i++) ::A[i] = A[i];
build();
}
int Query(int L, int R) {
return qry(L, R);
}
