Submission #1264570

#	Time	Username	Problem	Language	Result	Execution time	Memory
1264570		tminh	Curtains (NOI23_curtains)	C++20	100 / 100	661 ms	59396 KiB

curtains

#include "bits/stdc++.h"
using namespace std;

#define task ""
#define ll long long
#define endl '\n'
#define fi first
#define se second
#define vall(a) (a).begin(), (a).end()
#define sze(a) (int)a.size()
#define pii pair<int, int>
#define pll pair<ll, ll>


#define ep emplace_back
#define pb push_back
#define pf push_front


const ll mod = 1e9 + 7;
const int N = 5e5 + 5;
const int oo = 1e9;

bool START;


int n, q, m;
struct ST {
	int st[N << 2], lazy[N << 2];
	void push(int id) {
		st[id << 1] = max(lazy[id], st[id << 1]);
		st[id << 1 | 1] = max(lazy[id], st[id << 1 | 1]);
		
		lazy[id << 1] = max(lazy[id], lazy[id << 1]);
		lazy[id << 1 | 1] = max(lazy[id], lazy[id << 1 | 1]);
		lazy[id] = 0;
	}
	void update(int id, int l, int r, int u, int v, int val) {
		if (l > v || r < u) return;
		if (l >= u && r <= v) {
			st[id] = max(st[id], val);
			lazy[id] = max(lazy[id], val);
			return;
		}
		int mid = (l + r) >> 1;
		if (lazy[id]) push(id);
		update(id << 1, l, mid, u, v, val);
		update(id << 1 | 1, mid + 1, r, u, v, val);
		st[id] = min(st[id << 1], st[id << 1 | 1]);
	}
	int get(int id, int l, int r, int u, int v) {
		if (l > v || r < u) return oo;
		if (l >= u && r <= v) return st[id];
		int mid = (l + r) >> 1;
		if (lazy[id]) push(id);
		return min(get(id << 1, l, mid, u, v), get(id << 1 | 1, mid + 1, r, u, v));
	}
} st;


bool ans[N];
vector<int> sw[N];
vector<pii> qr[N];

inline void solve() {
	for (int r = 1; r <= n; ++r) {
		for (int l : sw[r]) st.update(1, 1, n, l, r, l);
		for (auto[l, id] : qr[r]) ans[id] = (st.get(1, 1, n, l, r) >= l);
	}
	for (int i = 1; i <= q; ++i) cout << (ans[i] ? "YES" : "NO") << endl;
}


inline void input() {
    cin >> n >> m >> q;
    for (int i = 1; i <= m; ++i) {
    	int l, r;
    	cin >> l >> r;
    	sw[r].pb(l);
    }
    for (int i = 1; i <= q; ++i) {
    	int l, r;
    	cin >> l >> r;
    	qr[r].pb(make_pair(l, i));
    }
    return solve();
}
bool END;

int main() {
    if(fopen(task ".inp", "r")) {
        freopen(task ".inp", "r", stdin);
        freopen(task ".out", "w", stdout);
    }
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);

    input();
    
    
    cerr << endl << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << 's' << endl;
    cerr << "Memory: " << fabs ((&END - &START)) / 1048576.0 << "MB\n";
    return 0;
}

Compilation message (stderr)

curtains.cpp: In function 'int main()':
curtains.cpp:92:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   92 |         freopen(task ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
curtains.cpp:93:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   93 |         freopen(task ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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