@[HEIMOFA](/user/929819)
```cpp
#include<bits/stdc++.h>
#define int long long
#define lowbit(x) x&-x
#define lc (x<<1)
#define rc (x<<1|1)
using namespace std;
int n,m,rt,sum,idx;
const int N=2e4+5;
int dfn[N],low[N],ans[N];
vector<int> g[N];
void Tarjan(int x){
dfn[x]=low[x]=++idx;
int len=g[x].size();
int son = 0 ;
for(int i=0;i<len;i++){
int y=g[x][i];
if(!dfn[y]){
Tarjan(y);
low[x]=min(low[x],low[y]);
if(low[y]>=dfn[x]){
son++;
if(son>1||x!=rt) ans[x]=1;
}
}
else low[x]=min(low[x],dfn[y]);
}
}
signed main()
{
scanf("%lld%lld",&n,&m);
for(int i=1;i<=m;i++){
int a,b;scanf("%lld%lld",&a,&b);
g[a].push_back(b);
g[b].push_back(a);
}
for(int i=1;i<=n;i++) if(!dfn[i]) rt=i,Tarjan(i);
for(int i=1;i<=n;i++) if(ans[i]) sum++;
printf("%lld\n",sum);
for(int i=1;i<=n;i++) if(ans[i]) printf("%lld ",i);
return 0;
}
```
计数点赋值位置改一下就好哩
by xiao__xiao @ 2024-01-25 16:39:30
@[xiao__xiao](/user/1015805) thx，当时不知道怎么想的……
by HEIMOFA @ 2024-01-25 16:42:46