제출 #655961

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
655961		Kahou	Port Facility (JOI17_port_facility)	C++14	10 / 100	16 ms	572 KiB

port_facility

#include<bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define endl '\n'
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int M = 1e9 + 7;
const int N = 1e6 + 50;
int n, L[N], R[N], par[N], sz[N], cnt;
set<pii> sl, sr;

int getroot(int u) {
        if (u == par[u]) return u;
        return par[u] = getroot(par[u]);
}
void uniset(int u, int v) {
        u = getroot(u), v = getroot(v);
        if (u == v) return;
        if (sz[u] < sz[v]) swap(u, v);
        par[v] = u;
        sz[u] += sz[v];
        cnt--;
}

void solve() {
        cin >> n;
        cnt = n;
        for (int i = 1; i <= n; i++) {
                cin >> L[i] >> R[i];
                sl.insert({L[i], i});
                sr.insert({R[i], i});
                par[i] = i;
                sz[i] = 1;
        }
        bool flg = 1;
        while (sr.size()) {
                int u = sr.begin()->S;
                sr.erase(sr.begin());
                sl.erase({L[u], u});

                int prv = 1e9;
                auto it = sl.lower_bound({L[u], 0});
                auto ed = sl.lower_bound({R[u], 0});
                for (; it != ed; it++) {
                        int v = it->S;
                        if (R[v] > prv) {
                                flg = 0;
                                break;
                        }
                        prv = R[v];
                        uniset(u, v);
                }

                if (!flg) break;
        }

        if (!flg) return cout << 0 << endl, void();

        int ans = 1;

        for (int i = 1; i <= cnt; i++) {
                ans <<= 1;
                if (ans >= M) ans -= M;
        }

        cout << ans << endl;
}

int main() {
        ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
        solve();
        return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 12
• Subtask 3: 0 / 56
• Subtask 4: 0 / 22