All problems were written and prepared by me.
You will be given 5 problems, and one of them is divided into two subtasks. You will have 2 hours to solve them.
I would like to thank:
irkstepanov for excellent coordination and Russian translation!
Golovanov399 for providing useful feedbacks.
kizen for helping me much with one problem of the contest.
ko_osaga for Nutella testing.
MikeMirzayanov for great Polygon and Codeforces platforms!
And last but not least, You for participating in the round!
Score distribution: $$$500 - 1000 - 1500 - 2000 - (2000 + 2000)$$$
Good luck and enjoy the round!
UPD: Editorial is out.
UPD2: Congratulations to the winners!
Official + Unofficial Contestants