Submission #1188976

#	Time	Username	Problem	Language	Result	Execution time	Memory
1188976		caterpillow	Curtains (NOI23_curtains)	C++20	100 / 100	855 ms	74912 KiB

curtains

#include <bits/stdc++.h>

using namespace std;

const int sz = 1 << 19;
struct LazySeg {
    vector<int> seg, lazy;
    LazySeg() : seg(2 * sz, -1), lazy(2 * sz, -1) {}
    void pull(int i) { seg[i] = min(seg[2 * i], seg[2 * i + 1]); }
    void push(int i) {
        seg[i] = max(seg[i], lazy[i]);
        if (i < sz) for (int j = 0; j < 2; j++) 
            lazy[2 * i + j] = max(lazy[2 * i + j], lazy[i]); 
        lazy[i] = -1;
    }
    void upd(int lo, int hi, int x, int i = 1, int l = 0, int r = sz) {
        push(i);
        if (lo >= r || hi <= l) return;
        if (lo <= l && r <= hi) {
            lazy[i] = max(lazy[i], x);
            push(i);
            return;
        }
        int m = (l + r) / 2;
        upd(lo, hi, x, 2 * i, l, m);
        upd(lo, hi, x, 2 * i + 1, m, r);
        pull(i);
    }
    int query(int lo, int hi, int i = 1, int l = 0, int r = sz) {
        push(i);
        if (lo >= r || hi <= l) return 1e9;
        if (lo <= l && r <= hi) return seg[i];
        int m = (l + r) / 2;
        return min(query(lo, hi, 2 * i, l, m), query(lo, hi, 2 * i + 1, m, r));
    }
};

main() {
    cin.tie(0)->sync_with_stdio(0);
    
    int n, m, q;
    cin >> n >> m >> q;
    LazySeg seg;

    vector<string> ans(q);
    vector<vector<int>> lefts(n + 1);
    vector<vector<pair<int, int>>> queries(n + 1);
    while (m--) {
        int l, r; cin >> l >> r;
        lefts[r].push_back(l - 1);
    }
    for (int i = 0; i < q; i++) {
        int l, r; cin >> l >> r;
        queries[r].push_back({l - 1, i});
    }

    for (int r = 1; r <= n; r++) {
        for (int l : lefts[r]) seg.upd(l, r, l);
        for (auto [l, i] : queries[r]) {
            ans[i] = seg.query(l, r) == l ? "YES" : "NO";
        }
    }
    for (string x : ans) cout << x << '\n';
}

Compilation message (stderr)

curtains.cpp:38:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   38 | main() {
      | ^~~~

• Subtask 1: 3 / 3
• Subtask 2: 6 / 6
• Subtask 3: 15 / 15
• Subtask 4: 20 / 20
• Subtask 5: 36 / 36
• Subtask 6: 20 / 20