Submission #959007

#	Time	Username	Problem	Language	Result	Execution time	Memory
959007		Cyber_Wolf	Pipes (CEOI15_pipes)	C++17	20 / 100	1745 ms	65536 KiB

pipes

#include <bits/stdc++.h>
 
using namespace std;
 
#define lg int
#define fastio ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
 
const lg N = 1e5+5;
 
vector<lg> adj[N];
lg n,m, low[N], tin[N], tmp, id;
set<array<lg, 2>> se;
 
void dfs(lg src, lg par = -1)
{
	tin[src] = low[src] = ++tmp;
	int idx = 0;
	for(auto it : adj[src])
	{
		if(it == par)
		{
			idx++;	
			continue;
		}
		if(tin[it])
		{
			low[src] = min(low[src], tin[it]);
			idx++;	
			continue;
		}
		dfs(it, src);
		low[src] = min(low[src], low[it]);
		if(idx && adj[src][idx-1] == it)	continue;
		if(idx+1 < adj[src].size() && adj[src][idx+1] == it)	continue;
		if(low[it] > tin[src])
		{
			cout << src << ' ' << it << '\n';
		}
		idx++;	
	}
}
 
int main()
{
	fastio;
	cin >> n >> m;
	for(int i = 0; i < m; i++)
	{
		lg u, v;
		cin >> u >> v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	for(int i = 1; i <= n; i++)	sort(adj[i].begin(), adj[i].end());
	for(int i = 1; i <= n; i++)
	{
		if(!tin[i])	dfs(i);
	}
 
    return 0;
}

Compilation message (stderr)

pipes.cpp: In function 'void dfs(int, int)':
pipes.cpp:34:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |   if(idx+1 < adj[src].size() && adj[src][idx+1] == it) continue;
      |      ~~~~~~^~~~~~~~~~~~~~~~~

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