貌似这题原来是初赛题（见 <https://www.luogu.com.cn/discuss/118833>），然后管理员把它改成了现在这题。
by TheSky233 @ 2022-12-18 17:52:07
@[TheSky233](/user/501865) 明白了，所以这题思路到底是什么呢qwq
by SJH_qwq @ 2022-12-18 18:01:45
@[songjiahao_](/user/761125) 双指针。
by Usada_Pekora @ 2022-12-18 18:14:16
@[Zyingyzzz](/user/434929) 啊什么这样的吗！
我不会()
by SJH_qwq @ 2022-12-18 18:15:29
@[songjiahao_](/user/761125) https://www.luogu.com.cn/blog/zyingy/solution-p1366
by Usada_Pekora @ 2022-12-18 18:29:32
@[Zyingyzzz](/user/434929) orz%%%%
by SJH_qwq @ 2022-12-18 18:43:09
@[songjiahao_](/user/761125) <https://www.luogu.com.cn/blog/501865/solution-p1366>
双指针写挂了 1h，去紫菜了
by TheSky233 @ 2022-12-18 19:34:50