Hello Codeforces!

I have a pleasure to invite you to Codeforces Round #647 (Div. 1) and Codeforces Round #647 (Div. 2). This round will take place on Thursday, June 4th, 2020, at 16:35. In both divisions, you will have 2.5 hours to solve 6 problems. Three of them will be shared.

The problems for this round were prepared by MicGor, Grzmot, Okrut, and me.

I would like to thank everyone who made this round possible:

• budalnik, for the excellent coordination

• Lewin, sstrong for invaluable advice and extensive testing

• KrK, yarek, -is-this-fft-, w0nsh, Marckess, Ari, Fortin, Dup4, craborac, 300iq for taking the time to test and providing useful feedback

• MikeMirzayanov for great platforms Codeforces and Polygon

We hope you will enjoy the problem set! Good luck!