摘要：
[洛谷传送门](https://www.luogu.com.cn/problem/AT_jsc2021_f "洛谷传送门") [AtCoder 传送门](https://atcoder.jp/contests/jsc2021/tasks/jsc2021_f "AtCoder 传送门") 我们考虑动态 阅读全文
摘要：
[洛谷传送门](https://www.luogu.com.cn/problem/CF1845C "洛谷传送门") [CF 传送门](https://codeforces.com/problemset/problem/1845/C "CF 传送门") 我怎么这么多天没写题解了，快来水一篇。 考虑对 阅读全文