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Over 20,000 problems available: AMC 8/10/12 and AIME problems from 2010-2024; USAJMO/USAMO problems from 2002-2024; USACO problems from 2014 to 2024 (all divisions); all Codeforces, AtCoder and DMOJ problems. If you leave the search field blank, it returns all problems with the specified type.

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  • AMC 8: [year] AMC 8 Problem #, Ex: 2013 AMC 8 Problem 1
  • AMC 10: [year] AMC 10A Problem # OR [year] AMC 10B Problem #, Ex: 2015 AMC 10A Problem 16
  • AMC 12: [year] AMC 12A Problem # OR [year] AMC 12B Problem #, Ex: 2021 AMC 12B Problem 25
  • AIME: [year] AIME I Problem # OR [year] AIME II Problem #, Ex: 2013 AIME I Problem 8
  • USAJMO/USAMO: [year] USAJMO/USAMO Problem #, Ex: 2023 USAJMO Problem 1
  • Codeforces: Codeforces [contest id (e.g. 101)][problem id (e.g. A, B, C)]: [Codeforces problem name], Ex: Codeforces 1336F: Journey
  • AtCoder: AtCoder [contest id (e.g. ABC314, ARC164, ZONE2021)]: [problem id (A, B, C)]. [Problem name], Ex: AtCoder ZONE2021: E. Sneaking
  • DMOJ: DMOJ [contest name (if applicable)] [problem number (e.g. P1)] - [Problem name], Ex: DMOJ Yet Another Contest 3 P1 - Shell Swap Scam
  • USACO: [year] [contest month (e.g. January, US Open)], [division (e.g. Gold)]: [Problem name], Ex: USACO 2023 US Open Contest, Bronze: Rotate and Shift

ID Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)
2050 Codeforces 474F: Ant colony
2049 Codeforces 474E: Pillars
2048 Codeforces 474D: Flowers
2047 Codeforces 474C: Captain Marmot
2046 Codeforces 474B: Worms
2045 Codeforces 474A: Keyboard
2044 Codeforces 472G: Design Tutorial: Increase the Constraints
2043 Codeforces 472F: Design Tutorial: Change the Goal
2042 Codeforces 472E: Design Tutorial: Learn from a Game
2041 Codeforces 472D: Design Tutorial: Inverse the Problem
2040 Codeforces 472C: Design Tutorial: Make It Nondeterministic
2039 Codeforces 472B: Design Tutorial: Learn from Life
2038 Codeforces 472A: Design Tutorial: Learn from Math
2037 Codeforces 471E: MUH and Lots and Lots of Segments
2036 Codeforces 471D: MUH and Cube Walls
2035 Codeforces 471C: MUH and House of Cards
2034 Codeforces 471B: MUH and Important Things
2033 Codeforces 471A: MUH and Sticks
2032 Codeforces 470H: Array Sorting
2031 Codeforces 470G: Hamming Distance
2030 Codeforces 470F: Pairwise Sums
2029 Codeforces 470E: Chessboard
2028 Codeforces 470D: Caesar Cipher
2027 Codeforces 470C: Eval
2026 Codeforces 470B: Hexakosioihexekontahexaphobia
2025 Codeforces 470A: Crystal Ball Sequence
2024 Codeforces 469B: Chat Online
2023 Codeforces 469A: I Wanna Be the Guy
2022 Codeforces 468E: Permanent
2021 Codeforces 468D: Tree
2020 Codeforces 468C: Hack it!
2019 Codeforces 468B: Two Sets
2018 Codeforces 468A: 24 Game
2017 Codeforces 467E: Alex and Complicated Task
2016 Codeforces 467D: Fedor and Essay
2015 Codeforces 467C: George and Job
2014 Codeforces 467B: Fedor and New Game
2013 Codeforces 467A: George and Accommodation
2012 Codeforces 466E: Information Graph
2011 Codeforces 466D: Increase Sequence
2010 Codeforces 466C: Number of Ways
2009 Codeforces 466B: Wonder Room
2008 Codeforces 466A: Cheap Travel
2007 Codeforces 465B: Inbox (100500)
2006 Codeforces 465A: inc ARG
2005 Codeforces 464E: The Classic Problem
2004 Codeforces 464D: World of Darkraft - 2
2003 Codeforces 464C: Substitutes in Number
2002 Codeforces 464B: Restore Cube
2001 Codeforces 464A: No to Palindromes!
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