~~这题不是线段树合并的板子么~~
by 1saunoya @ 2019-12-17 13:02:01
可以，虽然有更简单的做法（
by dengyaotriangle @ 2019-12-17 13:05:22
@[Isaunoya](/user/96580) orzhgs
by 土田共戈 @ 2019-12-17 13:07:26
@[dengyaotriangle](/user/62598) orz zjx
by momo5440 @ 2019-12-17 15:47:23
~~似乎还能用 set + 启发式合并做~~
by vectorwyx @ 2021-07-11 11:57:16