@[KMnO4](/space/show?uid=83614) 这题不是搜索 emm
by 顾z @ 2018-10-29 11:30:56
@[顾z](/space/show?uid=87960) 树上差分也可以吧...但是我还没写出来
by KMnO4 @ 2018-10-29 13:47:14
orz，顺便求lz树上差分思路
by Taduro @ 2018-11-02 14:43:50