确实是tarjan写错了
```cpp
if(!dfn[v]){
tarjan(v);
low[u] = min(low[u], dfn[v]);
//这一行要改成low[u] = min(low[u], low[v]);
}else if(instk[v]){
low[u] = min(low[u], dfn[v]);
}
```
by gcx12012 @ 2023-05-25 11:03:00
@[gcx12012](/user/494601) 谢谢啦
by XSean @ 2023-05-26 07:43:25