#include<bits/stdc++.h>
#include "secret.h"
using namespace std;
const int N = 1000;
int mem[N][N], memn;
void prec(int l, int r) {
if (l == r) return;
int m = (l + r) >> 1;
prec(l, m); prec(m + 1, r);
for (int i = m - 1; i >= l; --i) mem[i][m] = Secret(mem[i][i], mem[i + 1][m]);
for (int i = m + 2; i <= r; ++i) mem[m + 1][i] = Secret(mem[m + 1][i - 1], mem[i][i]);
}
void Init(int n, int a[]) {
for (int i = 0; i < n; ++i) mem[i][i] = a[i];
prec(0, n - 1);
memn = n;
}
int get(int tl, int tr, int l, int r) {
if (tl == tr) return mem[tl][tl];
int tm = (tl + tr) >> 1;
if (r <= tm) return get(tl, tm, l, r);
if (tm < l) return get(tm + 1, tr, l, r);
return Secret(mem[l][tm], mem[tm + 1][r]);
}
int Query(int l, int r) { return get(0, memn - 1, l, r); }
