//In the name of Allah
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
const int N = 1e5 + 10;
int par[2][N], mark[N], t;
vector < int > adj[N];
int getPar(int v){
return par[t][v] == v ? v : par[t][v] = getPar(par[t][v]);
}
bool merge(int u, int v){
u = getPar(u); v = getPar(v);
if (u == v)
return false;
par[t][u] = v;
return true;
}
void DFS(int v, int p = 0){
mark[v] = 1;
par[1][v] = N;
int cnt = 0;
for (int u : adj[v]){
if (u == p){
cnt ++;
continue;
}
if (mark[u])
par[1][v] = min(par[1][v], par[0][u]);
else{
par[0][u] = par[0][v] + 1;
DFS(u, v);
par[1][v] = min(par[1][v], par[1][u]);
}
}
if (p && cnt == 1 && par[0][p] < par[1][v])
cout << p << ' ' << v << '\n';
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int n, m;
cin >> n >> m;
for (int i = 0; i < N; i ++)
par[0][i] = par[1][i] = i;
for (int i = 0; i < m; i ++){
int u, v, f = 1;
cin >> u >> v;
t = 0;
if (merge(u, v)){
adj[u].pb(v);
adj[v].pb(u);
f = 0;
}
t = 1;
if (f && merge(u, v)){
adj[u].pb(v);
adj[v].pb(u);
}
}
memset(par, 0, sizeof par);
for (int v = 1; v <= n; v ++)
if (!mark[v])
DFS(v);
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
3456 KB |
Output is correct |
2 |
Correct |
3 ms |
3436 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
4076 KB |
Output is correct |
2 |
Correct |
7 ms |
3820 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
117 ms |
3948 KB |
Output is correct |
2 |
Correct |
115 ms |
3948 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
202 ms |
4992 KB |
Output is correct |
2 |
Correct |
250 ms |
4204 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
326 ms |
6124 KB |
Output is correct |
2 |
Correct |
291 ms |
6252 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
498 ms |
11116 KB |
Output is correct |
2 |
Correct |
409 ms |
7788 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
703 ms |
11928 KB |
Output is correct |
2 |
Correct |
671 ms |
9324 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
960 ms |
13804 KB |
Output is correct |
2 |
Correct |
922 ms |
8940 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1243 ms |
14004 KB |
Output is correct |
2 |
Correct |
1092 ms |
9296 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1395 ms |
14444 KB |
Output is correct |
2 |
Correct |
1279 ms |
11832 KB |
Output is correct |