Submission #953477

#	Time	Username	Problem	Language	Result	Execution time	Memory
953477		Darren0724	Port Facility (JOI17_port_facility)	C++17	0 / 100	2 ms	6492 KiB

port_facility

#include <bits/stdc++.h>
using namespace std;
#define LCBorz ios_base::sync_with_stdio(false); cin.tie(0);
#define int long long
#define all(x) x.begin(), x.end()
#define endl '\n'
const int N=200005;
const int INF=1e18;
const int mod=1e9+7;
vector<int> adj[N],vis(N);
void dfs(int k,int pa){
    vis[k]=1;
    for(int j:adj[k]){
        if(j==pa)continue;
        if(!vis[j]){
            dfs(j,k);
        }
        else {
            cout<<0<<endl;
            exit(0);
        }
    }
} 
int32_t main() {
    LCBorz;
    int n;cin>>n;
    vector<int> a(n),b(n);
    for(int i=0;i<n;i++){
        cin>>a[i]>>b[i];
    }
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            if(i==j)continue;
            int cnt=(a[j]>=a[i]&&a[j]<=b[i])+(b[j]>=a[i]&&b[j]<=b[i]);
            if(cnt==1){
                adj[i].push_back(j);
            }
        }
    }
    int ans=1;
    for(int i=0;i<n;i++){
        if(!vis[i]){
            ans=ans*2%mod;
            dfs(i,i);
        }
    }
    cout<<ans<<endl;
    

    return 0;
}

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