#include <bits/stdc++.h> #include "secret.h" using namespace std; const int maxn = 1e3+10; int n, num[maxn]; int suf[4*maxn][maxn], pref[4*maxn][maxn]; int get(int x, int y) { return Secret(x, y); } void build(int node, int l, int r) { if (l == r || r == l+1) return; int mid = (l+r)>>1; suf[node][mid-1] = get(num[mid-1], num[mid]); for (int i = mid-2; i >= l; i--) suf[node][i] = get(num[i], suf[node][i+1]); pref[node][mid+1] = num[mid+1]; for (int i = mid+2; i <= r; i++) pref[node][i] = get(pref[node][i-1], num[i]); build(2*node, l, mid); build(2*node+1, mid+1, r); } int query(int node, int l, int r, int a, int b) { if (r == l+1) return get(num[l], num[r]); int mid = (l+r)>>1; if (b < mid) return query(2*node, l, mid, a, b); else if (a > mid) return query(2*node+1, mid+1, r, a, b); else if (a == mid) return get(num[mid], pref[node][b]); else if (b == mid) return suf[node][a]; return get(suf[node][a], pref[node][b]); } void Init(int N, int A[]) { n = N; for (int i = 1; i <= n; i++) num[i] = A[i-1]; build(1, 1, n); } int Query(int L, int R) { if (L == R) return num[L+1]; return query(1, 1, n, L+1, R+1); }