1+ #include < bits/stdc++.h>
2+ #define ll long long
3+ #define INF 1e18
4+ using namespace std ;
5+ 6+ vector<vector<ll>> adj;
7+ vector<ll> low, discover;
8+ vector<bool > visited;
9+ set<ll> articulation_pts;
10+ ll timer = 0 ;
11+ 12+ 13+ void explore (ll u, ll p = 0 ) {
14+ visited[u] = true ;
15+ discover[u] = low[u] = ++timer;
16+ 17+ ll children = 0 ;
18+ for (ll v : adj[u]) {
19+ if (visited[v] == false ) {
20+ children++;
21+ explore (v,u);
22+ low[u] = min (low[u], low[v]);
23+ if (p == 0 and children > 1 ) {
24+ articulation_pts.insert (u);
25+ }
26+ if (p != 0 and low[v] >= discover[u]) {
27+ articulation_pts.insert (u);
28+ }
29+ }
30+ else if (v != p) {
31+ low[u] = min (low[u], discover[v]);
32+ }
33+ }
34+ }
35+ 36+ void dfs (ll n) {
37+ ll i;
38+ for (i = 1 ; i <= n; i++) {
39+ if (visited[i] == false ) {
40+ explore (i);
41+ }
42+ }
43+ }
44+ 45+ int main () {
46+ ll n, m, i, u, v;
47+ cin >> n >> m;
48+ adj.resize (n+1 );
49+ discover.resize (n+1 );
50+ low.resize (n+1 );
51+ visited.assign (n+1 ,false );
52+ 53+ for (i = 0 ; i < m; i++) {
54+ cin >> u >> v;
55+ adj[u].push_back (v);
56+ adj[v].push_back (u);
57+ }
58+ dfs (n);
59+ for (ll pt : articulation_pts) {
60+ cout << pt << endl;
61+ }
62+ return 0 ;
63+ }
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