Hi everybody,

In a few days there will be a Moscow Open Olympiad. This olympiad is prepared by Moscow Olympiad Scientific Committee that you may know by Moscow Olympiad in Programming, Moscow Team Olympiad, and Megapolis Olympiad (rounds 327, 342, 345, 376, 401, 433, 441, 466, 469, 507, 516, 541, 545, 567, 583, 594, 622, 626, 657, 680, 704, 707, 727, 751, 775, 802, 829, 852, ).

The Open Olympiad consists of the most interesting and difficult problems proposed by our authors' team. Therefore, we decided to conduct a non-rating mirror of the Olympiad on Codeforces. The Olympiad takes place in two rounds, each consisting of $$$4$$$ problems, not ordered by difficulty, and $$$5$$$ hours to solve them. For each problem, you can earn up to $$$100$$$ points, which are distributed among several subproblems with different restrictions, allowing participants to earn partial points. Evaluation is done in the IOI format, where the participant receives a full testing report on all tests in the Online subgroup during the competition. The feature of the Open Olympiad is that some problems have Offline subgroups, the results of which will only be available after the end of the competition.

The competition problems were created and prepared by Mangooste, vaaven, Tikhon228, ViktorSM, isaf27, TheEvilBird, sevlll777, Papaz239 and pakhomovee under the guidance of Ormlis, grphil and Andreeva Elena Vladimirovna.

Special thanks to MikeMirzayanov for the codeforces and polygon systems, which were used in preparing the problems for this Olympiad.

Many thanks to the Olympiad testers: dshindov, FelixDzerzhinsky, Adikolon, isaf27, adepteXiao, talant, AgafonovArtem, Dart-Xeyter, inhabitant, Kapt, Siberian, alexashkins, alexxela12345, Sweezy, v0s7er, MOHOXPOM, Titoffifee.

Good luck!