#include "secret.h"
#include<bits/stdc++.h>
using namespace std;
const int _N = 1e3 + 1;
int RR[_N][_N];// right[i][j] = query(j, i)
int LL[_N][_N]; // left[i][j] = query(i, j)
vector<int> temp;
int a[_N];
int n;
void build(int l,int r){
if(l + 1 < r){
int mid = (l + r + 1)/2;
assert(mid < r && l <= mid);
temp.push_back(mid);
RR[mid + 1][mid] = a[mid + 1];
for(int i = mid + 2;i<=r;i++){
RR[i][mid] = Secret(RR[i - 1][mid], a[i]);
}
LL[mid][mid] = a[mid];
for(int i = mid - 1;i>=0;i--){
LL[i][mid] = Secret(LL[i + 1][mid], a[i]);
}
build(l, mid);
build(mid, r);
}
}
void Init(int N, int A[]) {
for(int i = 0;i<N;i++)
a[i] = A[i];
build(1, N - 1);
}
int Query(int L, int R) {
if(L == R){
return a[L];
}
else if(L + 1 == R)
return Secret(a[L], a[R]);
else{
for(auto e : temp){
if(L <= e && e < R)return Secret(LL[L][e], RR[R][e]);
}
assert(false);
}
}
