标记数组？
by liwenxi114514 @ 2022-10-14 14:42:14
@[liwenxi110720](/user/661913) 啊？我太蒟了没听懂
by Dreamcatching @ 2022-10-15 07:51:38
应该打标记，用个map，否则会造成重复进队，然后就mle了
by CCF_Friend @ 2022-12-11 16:51:22