Hello, Codeforces!

I'm very glad to invite you to Codeforces Round 639 (Div. 1) and Codeforces Round 639 (Div. 2). This contest will take place on May/06/2020 17:35 (Moscow time). In both divisions, you will have 2 hours 15 minutes to solve 6 problems.

Of course, this round would not be possible without the help of many people, who I'd like to thank:

• isaf27, for coordinating this round and helping with solution ideas.
• My ICPC teammates Kuroni and strongoier, and coach cnh355, for encouraging me to pursue competitive programming.
• 300iq, antontrygubO_o, Ari, ffao, fpc_coder, gamegame, Kuroni, entropy07, McDic, richzli, and VilgefortzOfRoggeveen for testing and providing valuable feedback.
• MikeMirzayanov for providing the Codeforces and Monogon Polygon platforms.