| #3601 | On Average They're PurpleNorth Central NA Regional 2019 | |
| #3602 | Full Depth Morning ShowNorth Central NA Regional 2019 | |
| #3603 | This Ain't Your Grandpa's CheckerboardNorth Central NA Regional 2019 | |
| #3604 | Solar EnergyNorth Central NA Regional 2019 | |
| #3605 | No Thanks!Pacific Northwest Regional 2020Mid-Atlantic USA Regional 2020 | |
| #3606 | Painted CorridorsPacific Northwest Regional 2020Mid-Atlantic USA Regional 2020Mid-Central USA Regional 2020 | |
| #3607 | Basic BasisPacific Northwest Regional 2020Mid-Atlantic USA Regional 2020 | |
| #3608 | Derangement RotationsPacific Northwest Regional 2020 | |
| #3609 | Reconstruct SumPacific Northwest Regional 2020 | |
| #3610 | Kangaroo PartyPacific Northwest Regional 2020 | |
| #3611 | Smoothie StandMid-Central USA Regional 2020 | |
| #3612 | All in the FamilyEast Central NA Regional 2020 | |
| #3613 | Kinky Word SearchesEast Central NA Regional 2020 | |
| #3614 | Math TradeEast Central NA Regional 2020 | |
| #3615 | Oreperations ResearchEast Central NA Regional 2020 | |
| #3616 | Over the Hill, Part 1East Central NA Regional 2020 | |
| #3617 | Over the Hill, Part 2East Central NA Regional 2020 | |
| #3618 | A Rank ProblemEast Central NA Regional 2020 | |
| #3619 | Restroom MonitorEast Central NA Regional 2020 | |
| #3620 | Scholar's LawnEast Central NA Regional 2020 | |
| #3621 | Simply SudokuEast Central NA Regional 2020 | |
| #3622 | Weighty TomesEast Central NA Regional 2020 | |
| #3623 | Workers of the World Unite! Just Not Too Close.East Central NA Regional 2020 | |
| #3624 | ASCII ArtCroatian Programming Contest 2020 | |
| #3625 | Brzi BiljarCroatian Programming Contest 2020 | |
| #3626 | Carska CivilizacijaCroatian Programming Contest 2020 | |
| #3627 | Drugi DioCroatian Programming Contest 2020 | |
| #3628 | Ekstremna EkspedicijaCroatian Programming Contest 2020 | |
| #3629 | Fenomenalni FenjerCroatian Programming Contest 2020 | |
| #3630 | Gospodar GljivaCroatian Programming Contest 2020 | |
| #3631 | Hvalevrijedan HitacCroatian Programming Contest 2020 | |
| #3632 | Izvanredna IsplataCroatian Programming Contest 2020 | |
| #3633 | Jači JovsiCroatian Programming Contest 2020 | |
| #3634 | Klasična KarantenaCroatian Programming Contest 2020 | |
| #3635 | Aromatična avanturaCroatian Programming Contest 2021 | |
| #3636 | Bratski brojeviCroatian Programming Contest 2021 | |
| #3637 | Cjelobrojne crteCroatian Programming Contest 2021 | |
| #3638 | Drvene daščiceCroatian Programming Contest 2021 | |
| #3639 | Ekscentrična enkripcijaCroatian Programming Contest 2021 | |
| #3640 | Fleksibilan fikusCroatian Programming Contest 2021 | |
| #3641 | Grozne graniceCroatian Programming Contest 2021 | |
| #3642 | Hrskave hrstuleCroatian Programming Contest 2021 | |
| #3643 | Idilična ivicaCroatian Programming Contest 2021 | |
| #3644 | Još jačiCroatian Programming Contest 2021 | |
| #3645 | StopwatchRocky Mountain Regional 2020 | |
| #3646 | Arithmetic DecodingRocky Mountain Regional 2020 | |
| #3647 | Paper SnowflakesRocky Mountain Regional 2020 | |
| #3648 | Forced ChoiceRocky Mountain Regional 2020 | |
| #3649 | Interview QueueRocky Mountain Regional 2020 | |
| #3650 | ConquestRocky Mountain Regional 2020 | |
| #3651 | DistanceRocky Mountain Regional 2020 | |
| #3652 | Antimatter RainRocky Mountain Regional 2020 | |
| #3653 | Vaccine EfficacyRocky Mountain Regional 2020 | |
| #3654 | Pegs and LegsRocky Mountain Regional 2020 | |
| #3655 | Train BoardingRocky Mountain Regional 2020 | |
| #3656 | Piece of Cake!Rocky Mountain Regional 2019 | |
| #3657 | Fantasy DraftRocky Mountain Regional 2019 | |
| #3658 | Folding a CubeRocky Mountain Regional 2019 | |
| #3659 | Integer DivisionRocky Mountain Regional 2019 | |
| #3660 | HogwartsRocky Mountain Regional 2019 | |
| #3661 | MoleculesRocky Mountain Regional 2019 | |
| #3662 | TypoRocky Mountain Regional 2019 | |
| #3663 | The Biggest TriangleRocky Mountain Regional 2019 | |
| #3664 | Tired TerryRocky Mountain Regional 2019 | |
| #3665 | Watch LaterRocky Mountain Regional 2019 | |
| #3666 | Lost LineupRocky Mountain Regional 2019 | |
| #3667 | Accumulator BatteryNorthern Subregional 2018 | |
| #3668 | Building a StairNorthern Subregional 2018 | |
| #3669 | Counting StairsNorthern Subregional 2018 | |
| #3670 | Distinct SubstringsNorthern Subregional 2018 | |
| #3671 | Email DestructionNorthern Subregional 2018 | |
| #3672 | Forgotten LandNorthern Subregional 2018 | |
| #3673 | Generalized German QuotationNorthern Subregional 2018 | |
| #3674 | Halves Not EqualNorthern Subregional 2018 | |
| #3675 | Interactive Array GuessingNorthern Subregional 2018Interactive | |
| #3676 | Joined VesselsNorthern Subregional 2018 | |
| #3677 | Keyboard ConsensusNorthern Subregional 2018 | |
| #3678 | LED-led PathsNorthern Subregional 2018 | |
| #3679 | 楼房重建清华集训 2012 Day 1CTT 2012 Day 1 | |
| #3680 | 序列染色清华集训 2012 Day 1CTT 2012 Day 1 | |
| #3681 | 模积和清华集训 2012 Day 1CTT 2012 Day 1 | |
| #3682 | 长跑清华集训 2012 Day 2CTT 2012 Day 2 | |
| #3683 | 跨平面清华集训 2012 Day 2CTT 2012 Day 2 | |
| #3684 | 共点圆清华集训 2012 Day 2CTT 2012 Day 2 | |
| #3685 | 序列操作清华集训 2012 Day 3CTT 2012 Day 3 | |
| #3686 | 麻将清华集训 2012 Day 3CTT 2012 Day 3 | |
| #3687 | Boss 单挑战清华集训 2012 Day 3CTT 2012 Day 3 | |
| #3688 | 保护古迹清华集训 2012 Day 4CTT 2012 Day 4 | |
| #3689 | 树清华集训 2012 Day 4CTT 2012 Day 4 | |
| #3690 | 阳光清华集训 2012 Day 4CTT 2012 Day 4 | |
| #3696 | Easy MathSichuan Provincial 2015 | |
| #3697 | CarriesSichuan Provincial 2015 | |
| #3698 | CensorSichuan Provincial 2015 | |
| #3699 | Vertex CoverSichuan Provincial 2015 | |
| #3700 | RectangleSichuan Provincial 2015 | |