Submission #731330

#	Time	Username	Problem	Language	Result	Execution time	Memory
731330		esomer	Pipes (CEOI15_pipes)	C++17	20 / 100	980 ms	65536 KiB

pipes

#include<bits/stdc++.h>
 
using namespace std;
 
#define endl "\n"

typedef long long int ll;
 
const int MOD = 1e9 + 7;

vector<pair<int, int>> pipes;
int cnt = 1;

void DFS(int x, vector<vector<pair<int, int>>>& adj, vector<int>& vis, vector<int>& mn, int edge){
	vis[x] = cnt; mn[x] = cnt; cnt++;
	for(pair<int, int> pr : adj[x]){
		int node = pr.first;
		if(pr.second == edge) continue;
		if(vis[node] > 0){
			mn[x] = min(mn[x], vis[node]);
		}else{
			DFS(node, adj, vis, mn, pr.second);
			mn[x] = min(mn[x], mn[node]);
			if(mn[node] > vis[x]){
				pipes.push_back({node, x});
			}
		}
	}
}

void solve(){
	int n, m; cin >> n >> m;
	vector<vector<pair<int, int>>> adj(n);
	for(int i = 0; i < m; i++){
		int u, v; cin >> u >> v; u--; v--;
		adj[u].push_back({v, i}); adj[v].push_back({u, i});
	}
	vector<int> vis(n, 0);
	vector<int> mn(n, 0);
	for(int i = 0; i < n; i++){
		if(!vis[i]){
			DFS(i, adj, vis, mn, -1);
		}
	}
	for(auto p : pipes) cout << p.first + 1 << " " << p.second + 1 << endl;
}

signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    //~ int tt; cin >> tt;
    int tt = 1;
    for(int t = 1; t <= tt; t++){
        solve();
    }
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 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