The appearance of this blog is to appeal the CF official sentence for my 1999F code。

Attention!

Your solution 274818573 for the problem 1999F significantly coincides with solutions daoqi/274818573, Haz_Begonia/274828630. Such a coincidence is a clear rules violation. Note that unintentional leakage is also a violation. For example, do not use ideone.com with the default settings (public access to your code). If you have conclusive evidence that a coincidence has occurred due to the use of a common source published before the competition, write a comment to post about the round with all the details. More information can be found at http://mirror.codeforces.com/blog/entry/8790. Such violation of the rules may be the reason for blocking your account or other penalties. In case of repeated violations, your account may be blocked.

【Codeforces Round 964 (Div. 4)AK实录】https://www.bilibili.com/video/BV17iameiEN8?vd_source=958d8670804c24a04935dc3755fc300a

Because I happened to be recording this game, you can see that the code for my F was written by myself。