#include "secret.h"
#include <bits/stdc++.h>
using namespace std;
#define pii pair<int, int>
#define F first
#define S second
const int MAX_N = 1e3 + 5;
int n, a[MAX_N];
int pre[15][MAX_N];
int suf[15][MAX_N];
void dnc(int deg, int l, int r) {
if (l == r) {
suf[deg][l] = a[l];
return;
}
int mid = (l + r) / 2;
pre[deg][mid + 1] = a[mid + 1];
for (int i = mid + 2; i <= r; i++) {
pre[deg][i] = Secret(pre[deg][i - 1], a[i]);
}
suf[deg][mid] = a[mid];
for (int i = mid - 1; i >= l; i--) {
suf[deg][i] = Secret(a[i], suf[deg][i + 1]);
}
dnc(deg + 1, l, mid);
dnc(deg + 1, mid + 1, r);
}
void Init(int N, int A[]) {
n = N;
for (int i = 1; i <= n; i++) {
a[i] = A[i - 1];
}
dnc(1, 1, n);
}
pii get(int id, int l, int r, int u, int v) {
int mid = (l + r) / 2;
if (u <= mid && mid <= v) {
return {id, mid};
}
if (u > mid) {
return get(id + 1, mid + 1, r, u, v);
}
return get(id + 1, l, mid, u, v);
}
int Query(int L, int R) {
int l = L + 1;
int r = R + 1;
if (l == r) return a[l];
pii it = get(1, 1, n, l, r);
int deg = it.F;
int mid = it.S;
if (mid == r) {
return suf[deg][l];
}
// cout << deg << ' ' << mid << '\n';
return Secret(suf[deg][l], pre[deg][r]);
}
