Submission #948773

#	Time	Username	Problem	Language	Result	Execution time	Memory
948773		Aiperiii	Pipes (CEOI15_pipes)	C++14	40 / 100	2403 ms	31272 KiB

pipes

#include <bits/stdc++.h>
//#define int long long
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
using namespace std;
const int N=1e5+5;
int p[2][N],vis[N],tin[N],low[N];
vector <int> g[N];
int find_set(int i,int v){
    if(p[i][v]==v)return v;
    return p[i][v]=find_set(i,p[i][v]);
}
bool union_set(int i,int u,int v){
    if(find_set(i,u)==find_set(i,v))return false;
    p[i][u]=v;
    return true;
}
int t=0;
void dfs(int v,int p){
    vis[v]=1;
    t++;
    tin[v]=t;
    low[v]=t;
    bool ok=0;
    for(auto to : g[v]){
        if(p==to && !ok)ok=1;
        else if(vis[to])low[v]=min(low[v],tin[to]);
        else{
            dfs(to,v);
            low[v]=min(low[v],low[to]);
            if(low[to]>tin[v]){
                cout<<v<<" "<<to<<"\n";
            }
        }
    }
}
signed main(){
    ios_base::sync_with_stdio();
    cin.tie(0);cout.tie(0);
    int n,m;
    cin>>n>>m;
    for(int i=1;i<=n;i++){
        p[0][i]=i;
        p[1][i]=i;
    }
    int u,v;
    for(int i=0;i<m;i++){
        cin>>u>>v;
        if(union_set(0,u,v)){
            g[u].pb(v);
            g[v].pb(u);
        }
        else if(union_set(1,u,v)){
            g[u].pb(v);
            g[v].pb(u);
        }
    }
    for(int i=1;i<=n;i++){
        if(!vis[i])dfs(i,0);
    }
}

/*

 */

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10