I invite all of you to participate in regular Codeforces round #309 that will take place on 24 June, 19:30 MSK.
Some of you may know me as lg5293 on Topcoder (you can see some of my past problems here), but this is my first time ever writing a Codeforces round. I've designed all the problems myself and I hope you enjoy them.
I want to thank ctunoku for helping me come up with stories for the problems, Zlobober for his immense help with preparation for this round, winger for testing the problems, Delinur for translating statements, and of course MikeMirzayanov for the superb Codeforces and Polygon systems.
I hope to see you all at the round. Good luck and have fun! :)
UPD: Scoring will be dynamic. Problems will be arranged by what I think is increasing difficulty.
UPD: Editorial is here. Congratulations to the top 5: