1 |
P1 - Alternating Current |
Codeforces |
Codeforces Round #200 (Div. 1) & Codeforces Round #200 (Div. 2) |

2 |
P2 - New Year's Eve |
Codeforces |
Codeforces Round #456 (Div. 2) |

3 |
P3 - Hongcow Learns the Cyclic Shift |
Codeforces |
Codeforces Round #385 (Div. 2) |

4 |
P4 - Mind the Gap |
Codeforces |
Codeforces Round #477 (rated, Div. 2, based on VK Cup 2018 Round 3) |

5 |
P5 - Graph and String |
Codeforces |
AIM Tech Round (Div. 1) & AIM Tech Round (Div. 2) |

6 |
P6 - Writing Code |
Codeforces |
Codeforces Round #302 (Div. 1) & Codeforces Round #302 (Div. 2) |

7 |
P7 - Check the string |
Codeforces |
Divide by Zero 2018 and Codeforces Round #474 (Div. 1 + Div. 2, combined) |

8 |
P8 - Fight the Monster |
Codeforces |
Codeforces Round #278 (Div. 2) & Codeforces Round #278 (Div. 1) & Codeforces Round #278 (Div. 2) & Codeforces Round #278 (Div. 1) |

9 |
P9 - Tree Construction |
Codeforces |
Codeforces Round #353 (Div. 2) |

10 |
P10 - Cow Program |
Codeforces |
Codeforces Round #174 (Div. 1) & Codeforces Round #174 (Div. 2) |

11 |
P11 - Pashmak and Graph |
Codeforces |
Codeforces Round #261 (Div. 2) |

12 |
P12 - DZY Loves Physics |
Codeforces |
Codeforces Round #254 (Div. 1) & Codeforces Round #254 (Div. 2) |

13 |
P13 - The Meeting Place Cannot Be Changed |
Codeforces |
?????????? 2017 - ????? (?????? ??? ??????-??????????) |

14 |
P14 - Gerald and Giant Chess |
Codeforces |
Codeforces Round #313 (Div. 1) & Codeforces Round #313 (Div. 2) |

15 |
P15 - Santa Claus and Robot |
Codeforces |
Technocup 2017 - Elimination Round 3 |

16 |
P16 - Wilbur and Points |
Codeforces |
Codeforces Round #331 (Div. 2) |

17 |
P17 - Count Good Substrings |
Codeforces |
Codeforces Round #258 (Div. 2) |

18 |
P18 - Coloring a Tree |
Codeforces |
Codeforces Round #453 (Div. 2) |

19 |
P19 - Fools and Roads |
Codeforces |
Codeforces Round #121 (Div. 1) & Codeforces Round #121 (Div. 2) |

20 |
P20 - Months and Years |
Codeforces |
Codeforces Round #452 (Div. 2) |

21 |
P21 - Almost Identity Permutations |
Codeforces |
Educational Codeforces Round 32 |

22 |
P22 - New Year and Fireworks |
Codeforces |
Good Bye 2016 |

23 |
P23 - Two Sets |
Codeforces |
Codeforces Round #268 (Div. 1) & Codeforces Round #268 (Div. 2) |

24 |
P24 - Vanya and Scales |
Codeforces |
Codeforces Round #308 (Div. 2) |

25 |
P25 - Maximum Number |
Codeforces |
VK Cup 2017 - Wild Card Round 1 |

26 |
P26 - Name Quest |
Codeforces |
VK Cup 2015 - Qualification Round 2 |

27 |
P27 - Useful Decomposition |
Codeforces |
Avito Code Challenge 2018 |

28 |
P28 - New Year Table |
Codeforces |
Codeforces Round #100 |

29 |
P29 - Santa Claus and Candies |
Codeforces |
Testing Round #13 |

30 |
P30 - Nephren gives a riddle |
Codeforces |
Codeforces Round #449 (Div. 1) & Codeforces Round #449 (Div. 2) |

31 |
P31 - Office Keys |
Codeforces |
Codeforces Round #424 (Div. 1, rated, based on VK Cup Finals) & Codeforces Round #424 (Div. 2, rated, based on VK Cup Finals) |

32 |
P32 - Little Elephant and Interval |
Codeforces |
Codeforces Round #129 (Div. 1) & Codeforces Round #129 (Div. 2) |

33 |
P33 - 2-3-numbers |
Codeforces |
VK Cup 2018 - Wild-card Round 1 |

34 |
P34 - Keyboard Layouts |
Codeforces |
Codeforces Round #424 (Div. 2, rated, based on VK Cup Finals) |

35 |
P35 - Micro-World |
Codeforces |
Educational Codeforces Round 45 (Rated for Div. 2) |

36 |
P36 - Arpa’s obvious problem and Mehrdad’s terrible solution |
Codeforces |
Codeforces Round #383 (Div. 2) |

37 |
P37 - Mind the Gap |
Codeforces |
Codeforces Round #477 (rated, Div. 2, based on VK Cup 2018 Round 3) |

38 |
P38 - Minesweeper |
Codeforces |
Codeforces Round #483 (Div. 2) [Thanks, Botan Investments and Victor Shaburov!] |

39 |
P39 - Find Extra One |
Codeforces |
Codeforces Round #450 (Div. 2) |

40 |
P40 - Drazil and His Happy Friends |
Codeforces |
Codeforces Round #292 (Div. 1) & Codeforces Round #292 (Div. 2) & Codeforces Round #292 (Div. 1) & Codeforces Round #292 (Div. 2) |

41 |
P41 - Tritonic Iridescence |
Codeforces |
Codeforces Round #472 (rated, Div. 2, based on VK Cup 2018 Round 2) |

42 |
P42 - Money Transfers |
Codeforces |
Codeforces Round #353 (Div. 2) |

43 |
P43 - Mike and Feet |
Codeforces |
Codeforces Round #305 (Div. 1) & Codeforces Round #305 (Div. 2) |

44 |
P44 - Remainders Game |
Codeforces |
Codeforces Round #360 (Div. 1) & Codeforces Round #360 (Div. 2) |

45 |
P45 - DNA Alignment |
Codeforces |
Codeforces Round #295 (Div. 2) & Codeforces Round #295 (Div. 1) |

46 |
P46 - Pseudorandom Sequence Period |
Codeforces |
Croc Champ 2012 - Qualification Round |

47 |
P47 - Bear and Forgotten Tree 3 |
Codeforces |
VK Cup 2016 - Round 1 |

48 |
P48 - Polycarp at the Radio |
Codeforces |
Codeforces Round #375 (Div. 2) |

49 |
P49 - Classroom Watch |
Codeforces |
Codeforces Round #441 (Div. 1, by Moscow Team Olympiad) & Codeforces Round #441 (Div. 2, by Moscow Team Olympiad) |

50 |
P50 - Substring |
Codeforces |
Codeforces Round #460 (Div. 2) |