Submission #244348

#	Time	Username	Problem	Language	Result	Execution time	Memory
244348		Osama_Alkhodairy	Port Facility (JOI17_port_facility)	C++17	22 / 100	6055 ms	43896 KiB

port_facility

#include <bits/stdc++.h>
using namespace std;
#define finish(x) return cout << x << endl, 0
#define ll long long

const int N = 1000001;

int n, vis[N], mod = 1e9 + 7;
vector <pair <int, int> > a;
vector <int> v[N];

void dfs(int node){
    for(auto &i : v[node]){
        if(vis[i] != -1 && vis[i] != (vis[node] ^ 1)){
            cout << 0 << endl;
            exit(0);
        }
        if(vis[i] != -1) continue;
        vis[i] = vis[node] ^ 1;
        dfs(i);
    }
}
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    memset(vis, -1, sizeof vis);
    cin >> n;
    a.resize(n);
    for(auto &i : a) cin >> i.first >> i.second;
    for(int i = 0 ; i < n ; i++){
        for(int j = i + 1 ; j < n ; j++){
            pair <int, int> intr = make_pair(max(a[i].first, a[j].first), min(a[i].second, a[j].second));
            if(intr.second < intr.first) continue;
            if(intr == a[i] || intr == a[j]) continue;
            v[i].push_back(j);
            v[j].push_back(i);
        }
    }
    int ans = 1;
    for(int i = 0 ; i < n ; i++){
        if(vis[i] != -1) continue;
        ans *= 2;
        if(ans >= mod) ans -= mod;
        vis[i] = 0;
        dfs(i);
    }
    cout << ans << endl;
}

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