#define taskname "" #include <bits/stdc++.h> using namespace std; const int kMaxN = 200005; const int kMaxAi = 200005; const int kMaxLog = 19; int n, q, p[kMaxN], root[kMaxN]; struct PersistentSegmentTree { struct Node { int left_child = 0, right_child = 0; int sum = 0; }; vector<Node> st; int total_nodes = 0; PersistentSegmentTree() {} PersistentSegmentTree(int sz) { st.resize(sz + 1); } int NewNode(int m) { st[++total_nodes] = st[m]; return total_nodes; } int Update(int node_id, int l, int r, int pos, int val) { node_id = NewNode(node_id); if (l == r) { st[node_id].sum += val; } else { int mid = (l + r) / 2; if (pos <= mid) { st[node_id].left_child = Update(st[node_id].left_child, l, mid, pos, val); } else { st[node_id].right_child = Update(st[node_id].right_child, mid + 1, r, pos, val); } st[node_id].sum = st[st[node_id].left_child].sum + st[st[node_id].right_child].sum; } return node_id; } int Query(int node_id, int l, int r, int ql, int qr) { if (qr < l || ql > r) { return 0; } if (ql <= l && r <= qr) { return st[node_id].sum; } int mid = (l + r) / 2; return Query(st[node_id].left_child, l, mid, ql, qr) + Query(st[node_id].right_child, mid + 1, r, ql, qr); } } tree; int main() { if (fopen(taskname".inp", "r")) { freopen(taskname".inp", "r", stdin); freopen(taskname".out", "w", stdout); } ios_base::sync_with_stdio(false); cin.tie(nullptr); cin >> n >> q; for (int i = 1; i <= n; i++) { cin >> p[i]; } tree = PersistentSegmentTree(kMaxLog * kMaxAi); for (int i = 1; i <= n; i++) { root[i] = tree.Update(root[i - 1], 1, kMaxAi, p[i], 1); } while (q--) { int l, r; cin >> l >> r; int low = 1, high = kMaxAi, result; while (low <= high) { int mid = (low + high) / 2; if (tree.Query(root[r], 1, kMaxAi, mid, kMaxAi) - tree.Query(root[l - 1], 1, kMaxAi, mid, kMaxAi) >= mid) { result = mid, low = mid + 1; } else { high = mid - 1; } } cout << result << '\n'; } return 0; }

index.cpp: In function 'int main()':
index.cpp:59:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |     freopen(taskname".inp", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
index.cpp:60:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |     freopen(taskname".out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~