#include "secret.h"
int n;
int dnc[1007][1007];
void go(int l, int r, int A[]) {
int mid = (l + r) >> 1;
dnc[mid][mid] = A[mid];
dnc[mid + 1][mid + 1] = A[mid + 1];
for (int i = mid - 1; i >= l; --i) {
dnc[mid][i] = Secret(dnc[mid][i + 1], A[i]);
}
for (int i = mid + 2; i <= r; ++i) {
dnc[mid + 1][i] = Secret(dnc[mid + 1][i - 1], A[i]);
}
if (l < mid) go(l, mid - 1, A);
if (mid + 1 < r) go(mid + 2, r, A);
}
void Init(int N, int A[]) {
n = N;
go(0, n - 1, A);
}
int Query(int L, int R) {
int a = 0, b = n - 1;
while (a != b) {
int mid = (a + b) >> 1;
if (L <= mid and mid < R) {
return Secret(dnc[mid][L], dnc[mid + 1][R]);
} else if (mid == R) {
return dnc[mid][L];
} else if (mid < L) {
a = mid + 1;
} else {
b = mid;
}
}
return dnc[a][a];
}
