(所以dalao您的树链剖分错在哪里(吸取一下经验qwq
by histcat @ 2022-07-22 08:53:18
@[histcat](/user/361592) az,
dfn序时应判断
```cpp
if(dfn[top[u]]<dfn[top[v]])
```
我一开始写成了
```cpp
if(dfn[u]<dfn[v]
by 崔化博 @ 2022-07-22 08:56:32
@[崔化博](/user/304524) 哦哦谢谢dalaoqwq
by histcat @ 2022-07-22 08:59:15