Submission #930889

#	Time	Username	Problem	Language	Result	Execution time	Memory
930889		vjudge1	Curtains (NOI23_curtains)	C++17	100 / 100	831 ms	80328 KiB

curtains

#include <iostream>
#include <vector>
#include <cstring>
using namespace std;
int t[2000005], tt[2000005], res[500005];
vector<int> g[500005];
vector<pair<int, int>> gg[500005];
void update(int v, int tl, int tr, int l, int r, int x) {
    if (l > r) return;
    if (tl == l && r == tr) {
        t[v] = min(t[v], x);
        tt[v] = min(tt[v], x);
        return;
    }
    int mid = (tl + tr) / 2;
    update(v * 2, tl, mid, l, min(r, mid), x);
    update(v * 2 + 1, mid + 1, tr, max(l, mid + 1), r, x);
    t[v] = min(max(t[v * 2], t[v * 2 + 1]), tt[v]);
}
int sum(int v, int tl, int tr, int l, int r) {
    if (l > r) return 1e9 + 1;
    if (tl == l && tr == r) {
        return t[v];
    }
    int mid = (tl + tr) / 2;
    int h = sum(v * 2, tl, mid, l, min(r, mid)), k = sum(v * 2 + 1, mid + 1, tr, max(l, mid + 1), r);
    if (h == 1e9 + 1) return min(k, tt[v]);
    if (k == 1e9 + 1) return min(h, tt[v]);
    return min(max(h, k), tt[v]);
}
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int n, m, q;
    cin >> n >> m >> q;
    for (int i = 1; i <= m; i++) {
        int u, v;
        cin >> u >> v;
        g[u].push_back(v);
    }
    for (int i = 0; i < q; i++) {
        int u, v;
        cin >> u >> v;
        gg[u].push_back({v, i});
    }
    for (int i = 1; i <= n * 4; i++) t[i] = tt[i] = 1e9;
    for (int i = n; i >= 1; i--) {
        for (int w : g[i]) {
            update(1, 1, n, i, w, w);
        }
        for (auto w : gg[i]) {
            if (sum(1, 1, n, i, w.first) <= w.first) {
                res[w.second] = 1;
            }
        }
    }
    for (int i = 0; i < q; i++) {
        if (res[i] == 0) cout << "NO";
        else cout << "YES";
        cout << '\n';
    }
}

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