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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)
4200 Codeforces 985E: Pencils and Boxes
4199 Codeforces 985D: Sand Fortress
4198 Codeforces 985C: Liebig's Barrels
4197 Codeforces 985B: Switches and Lamps
4196 Codeforces 985A: Chess Placing
4195 Codeforces 984B: Minesweeper
4194 Codeforces 984A: Game
4193 Codeforces 983E: NN country
4192 Codeforces 983D: Arkady and Rectangles
4191 Codeforces 983C: Elevator
4190 Codeforces 983B: XOR-pyramid
4189 Codeforces 983A: Finite or not?
4188 Codeforces 982F: The Meeting Place Cannot Be Changed
4187 Codeforces 982E: Billiard
4186 Codeforces 982D: Shark
4185 Codeforces 982C: Cut 'em all!
4184 Codeforces 982B: Bus of Characters
4183 Codeforces 982A: Row
4182 Codeforces 981H: K Paths
4181 Codeforces 981G: Magic multisets
4180 Codeforces 981F: Round Marriage
4179 Codeforces 981E: Addition on Segments
4178 Codeforces 981D: Bookshelves
4177 Codeforces 981C: Useful Decomposition
4176 Codeforces 981B: Businessmen Problems
4175 Codeforces 981A: Antipalindrome
4174 Codeforces 980F: Cactus to Tree
4173 Codeforces 980E: The Number Games
4172 Codeforces 980D: Perfect Groups
4171 Codeforces 980C: Posterized
4170 Codeforces 980B: Marlin
4169 Codeforces 980A: Links and Pearls
4168 Codeforces 979E: Kuro and Topological Parity
4167 Codeforces 979D: Kuro and GCD and XOR and SUM
4166 Codeforces 979C: Kuro and Walking Route
4165 Codeforces 979B: Treasure Hunt
4164 Codeforces 979A: Pizza, Pizza, Pizza!!!
4163 Codeforces 978G: Petya's Exams
4162 Codeforces 978F: Mentors
4161 Codeforces 978E: Bus Video System
4160 Codeforces 978D: Almost Arithmetic Progression
4159 Codeforces 978C: Letters
4158 Codeforces 978B: File Name
4157 Codeforces 978A: Remove Duplicates
4156 Codeforces 977F: Consecutive Subsequence
4155 Codeforces 977E: Cyclic Components
4154 Codeforces 977D: Divide by three, multiply by two
4153 Codeforces 977C: Less or Equal
4152 Codeforces 977B: Two-gram
4151 Codeforces 977A: Wrong Subtraction
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