你change函数里第一行
```cpp
tree[p].dat+=(l-r+1)*cnum
```
应该改为
```cpp
tree[p].dat+=(r-l+1)*cnum
```
by Anli_li_father @ 2023-07-03 13:34:18
Ohhh
谢谢，orz
抱歉现在才看到
by TheIceStar @ 2023-07-03 16:46:13
已关注
by TheIceStar @ 2023-07-03 16:46:58