Submission #655967

#	Time	Username	Problem	Language	Result	Execution time	Memory
655967		Kahou	Port Facility (JOI17_port_facility)	C++14	0 / 100	0 ms	340 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 mod = 1e9 + 7;
int mul(int a, int b) {
        return 1ll*a*b%mod;
}
int pw(int a, int b) {
        int out = 1;
        while (b) {
                if (b&1) out = mul(out, a);
                a = mul(a,a);
                b>>=1;
        }
        return out; 
}


const int N = 1e6 + 50;
int n, L[N], R[N], par[N], sz[N], cnt;

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];
                par[i] = i;
                sz[i] = 1;
        }

        for (int i = 1; i <= n; i++) {
                for (int j = 1; j <= n; j++) {
                        if (L[i] < L[j] && L[j] < R[i] && R[i] < R[j]) {
                                if (getroot(i) == getroot(j)) {
                                        cout << 0 << endl;
                                        return;
                                }

                                uniset(i, j);
                        }
                }
        }
        cout << pw(2, cnt) << endl;
}

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

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