| #4801 | The PoolPetrozavodsk Summer 2022 Day 2 | |
| #4802 | Ternary SearchPetrozavodsk Summer 2022 Day 2 | |
| #4803 | CandiesPetrozavodsk Summer 2022 Day 2 | |
| #4804 | Regular ExpressionPetrozavodsk Summer 2022 Day 2 | |
| #4805 | Grammy SortingPetrozavodsk Summer 2022 Day 2 | |
| #4806 | Suffix SortPetrozavodsk Summer 2022 Day 2 | |
| #4807 | Melborp LacissalcPetrozavodsk Summer 2022 Day 2 | |
| #4808 | Great PartyPetrozavodsk Summer 2022 Day 2 | |
| #4809 | Maximum RangePetrozavodsk Summer 2022 Day 2 | |
| #4810 | Add OnePetrozavodsk Summer 2022 Day 3 | |
| #4811 | Be CarefulPetrozavodsk Summer 2022 Day 3 | |
| #4812 | Counting SequencePetrozavodsk Summer 2022 Day 3 | |
| #4813 | DS Team SelectionPetrozavodsk Summer 2022 Day 3 | |
| #4814 | Exciting TravelPetrozavodsk Summer 2022 Day 3 | |
| #4815 | Flower's LandPetrozavodsk Summer 2022 Day 3 | |
| #4816 | GamesPetrozavodsk Summer 2022 Day 3 | |
| #4817 | Half PlanePetrozavodsk Summer 2022 Day 3 | |
| #4818 | Inverse Line GraphPetrozavodsk Summer 2022 Day 3 | |
| #4819 | Just Another Number Theory ProblemPetrozavodsk Summer 2022 Day 3 | |
| #4820 | Kitten's ComputerPetrozavodsk Summer 2022 Day 3 | |
| #4821 | Long: WCWBTTPetrozavodsk Summer 2022 Day 3Interactive | |
| #4822 | Matrix CountingPetrozavodsk Summer 2022 Day 3 | |
| #4823 | No!Petrozavodsk Summer 2022 Day 3 | |
| #4824 | Bracket-and-bar SequencesPetrozavodsk Summer 2022 Day 4Communication | |
| #4825 | Even and Odd CombinationsPetrozavodsk Summer 2022 Day 4Communication | |
| #4826 | Find the PartsPetrozavodsk Summer 2022 Day 4Communication | |
| #4827 | Message Made of NoisePetrozavodsk Summer 2022 Day 4Communication | |
| #4828 | Four Plus FourPetrozavodsk Summer 2022 Day 4Communication | |
| #4829 | Mark on a GraphPetrozavodsk Summer 2022 Day 4Communication | |
| #4830 | Transfer of DutyPetrozavodsk Summer 2022 Day 4Communication | |
| #4831 | Eager SortingPetrozavodsk Summer 2022 Day 4Communication | |
| #4832 | TelepathyPetrozavodsk Summer 2022 Day 4Communication | |
| #4833 | Tetra-puzzlePetrozavodsk Summer 2022 Day 4Communication | |
| #4834 | TrijectionPetrozavodsk Summer 2022 Day 4Communication | |
| #4835 | ModePetrozavodsk Summer 2022 Day 5 | |
| #4836 | TreePetrozavodsk Summer 2022 Day 5 | |
| #4837 | RamenPetrozavodsk Summer 2022 Day 5 | |
| #4838 | Rotate Sum 2Petrozavodsk Summer 2022 Day 5 | |
| #4839 | Smaller LCAPetrozavodsk Summer 2022 Day 5 | |
| #4840 | NoodlePetrozavodsk Summer 2022 Day 5 | |
| #4841 | GeometryPetrozavodsk Summer 2022 Day 5 | |
| #4842 | Rectangle PlacementPetrozavodsk Summer 2022 Day 5 | |
| #4843 | Infectious DiseasePetrozavodsk Summer 2022 Day 5 | |
| #4844 | Positive StringPetrozavodsk Summer 2022 Day 5 | |
| #4845 | DFSPetrozavodsk Summer 2022 Day 5 | |
| #4846 | AgresorCroatian Programming Contest 2012 | |
| #4847 | KreditnaCroatian Programming Contest 2012 | |
| #4848 | KvadratiCroatian Programming Contest 2012 | |
| #4849 | LubeniceCroatian Programming Contest 2012 | |
| #4850 | MatematikaCroatian Programming Contest 2012 | |
| #4851 | PermutacijeCroatian Programming Contest 2012 | |
| #4852 | RestoraniCroatian Programming Contest 2012 | |
| #4853 | TartufiCroatian Programming Contest 2012 | |
| #4854 | VirusCroatian Programming Contest 2012 | |
| #4855 | Puzzle: X-Sums SudokuPetrozavodsk Summer 2022 Day 6 | |
| #4856 | Puzzle: Patrick's ParaboxPetrozavodsk Summer 2022 Day 6 | |
| #4857 | Puzzle: HearthstonePetrozavodsk Summer 2022 Day 6 | |
| #4858 | Poker Game: DecisionPetrozavodsk Summer 2022 Day 6 | |
| #4859 | Poker Game: ConstructionPetrozavodsk Summer 2022 Day 6 | |
| #4860 | Longest Common SubsequencePetrozavodsk Summer 2022 Day 6 | |
| #4861 | Lexicographic ComparisonPetrozavodsk Summer 2022 Day 6 | |
| #4862 | Expression EvaluationPetrozavodsk Summer 2022 Day 6 | |
| #4863 | Equivalence in ConnectivityPetrozavodsk Summer 2022 Day 6 | |
| #4864 | Symmetry: TreePetrozavodsk Summer 2022 Day 6 | |
| #4865 | Symmetry: ConvexPetrozavodsk Summer 2022 Day 6 | |
| #4866 | Symmetry: ClosurePetrozavodsk Summer 2022 Day 6 | |
| #4867 | So Easy!2013 Hunan Invitational | |
| #4868 | Circle Game2013 Hunan Invitational | |
| #4869 | Brilliant Programmers Show2013 Hunan Invitational | |
| #4870 | Hunter2013 Hunan Invitational | |
| #4871 | Special equations2013 Hunan Invitational | |
| #4872 | Multi-bit Trie2013 Hunan Invitational | |
| #4873 | Travel in time2013 Hunan Invitational | |
| #4874 | Bottles Arrangement2013 Hunan Invitational | |
| #4875 | Throw the Stones2013 Hunan Invitational | |
| #4876 | Bombs2013 Hunan Invitational | |
| #4877 | Changsha Marathon2013 Hunan Invitational | |
| #4878 | Easy ProblemPetrozavodsk Summer 2022 Day 7 | |
| #4879 | Standard ProblemPetrozavodsk Summer 2022 Day 7 | |
| #4880 | Network TransferPetrozavodsk Summer 2022 Day 7 | |
| #4881 | Hard ProblemPetrozavodsk Summer 2022 Day 7 | |
| #4882 | String Strange SumPetrozavodsk Summer 2022 Day 7 | |
| #4883 | Bayan TestingPetrozavodsk Summer 2022 Day 7 | |
| #4884 | Battleship: New RulesPetrozavodsk Summer 2022 Day 7 | |
| #4885 | Triangular Cactus PathsPetrozavodsk Summer 2022 Day 7 | |
| #4886 | Best SunPetrozavodsk Summer 2022 Day 7 | |
| #4887 | Fast BridgesPetrozavodsk Summer 2022 Day 7 | |
| #4888 | Decoding The MessagePetrozavodsk Summer 2022 Day 7 | |
| #4889 | 愚蠢的在线法官2021 集训队互测 Round 1 | |
| #4890 | 这是一道集训队胡策题2021 集训队互测 Round 1 | |
| #4891 | 树上的孤独2021 集训队互测 Round 1 | |
| #4892 | 序列2021 集训队互测 Round 2 | |
| #4893 | Imbalance2021 集训队互测 Round 2 | |
| #4894 | 学姐买瓜2021 集训队互测 Round 2 | |
| #4895 | Lovely Dogs2021 集训队互测 Round 3 | |
| #4896 | Alice、Bob 与 DFS2021 集训队互测 Round 3 | |
| #4897 | 音符大师2021 集训队互测 Round 3 | |
| #4898 | 基础图论练习题2021 集训队互测 Round 4 | |
| #4899 | 机器2021 集训队互测 Round 4 | |
| #4900 | 数列重排2021 集训队互测 Round 4 | |