#include<bits/stdc++.h>
using namespace std;
//#define int long long
#define F first
#define S second
#define pii pair<int,int>
#define mpr make_pair
typedef long long ll;
const int maxn = 1e5+10;
const int mod = 1e9+7;
const ll inf = 1e9+10;
int n, m;
vector<int> g[maxn];
bitset<maxn> mark;
int h[maxn], lo[maxn], Root;
vector<pii> ans;
void dfs(int v, int p = -1)
{
mark[v] = 1;
lo[v] = inf;
for(auto u : g[v]) if(mark[u] && u != p) lo[v] = min(lo[v],h[u]);
for(auto u : g[v])
if(!mark[u])
{
h[u] = h[v] + 1;
dfs(u,v);
lo[v] = min(lo[v], lo[u]);
}
if(v != Root && lo[v] >= h[v]) ans.push_back({v,p});
}
signed main()
{
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin>> n >> m;
for(int i = 1, u, v; i <= m; i++)
{
cin>> u >> v;
g[u].push_back(v);
g[v].push_back(u);
}
for(int i = 1; i <= n; i++)
if(!mark[i]) {Root = i; dfs(i);}
for(auto e : ans) cout<< e.F <<" "<< e.S <<"\n";
}
/*
10 11
1 7
1 8
1 6
2 8
6 7
5 8
2 5
2 3
2 4
3 4
10 9
*/
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
2688 KB |
Output is correct |
2 |
Incorrect |
2 ms |
2688 KB |
Wrong number of edges |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
3328 KB |
Output is correct |
2 |
Incorrect |
6 ms |
3072 KB |
Wrong number of edges |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
139 ms |
16280 KB |
Output is correct |
2 |
Correct |
136 ms |
15480 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
279 ms |
23832 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
537 ms |
41208 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
899 ms |
51192 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
1447 ms |
65536 KB |
Memory limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
1951 ms |
65540 KB |
Execution killed with signal 9 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
2385 ms |
65540 KB |
Execution killed with signal 9 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
2516 ms |
65536 KB |
Execution killed with signal 9 |
2 |
Halted |
0 ms |
0 KB |
- |