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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)
900 Codeforces 188H: Stack
899 Codeforces 188G: Array Sorting
898 Codeforces 188F: Binary Notation
897 Codeforces 188E: HQ9+
896 Codeforces 188D: Asterisks
895 Codeforces 188C: LCM
894 Codeforces 188B: A + Reverse B
893 Codeforces 188A: Hexagonal Numbers
892 Codeforces 187E: Heaven Tour
891 Codeforces 187D: BRT Contract
890 Codeforces 187C: Weak Memory
889 Codeforces 187B: AlgoRace
888 Codeforces 187A: Permutations
887 Codeforces 186B: Growing Mushrooms
886 Codeforces 186A: Comparing Strings
885 Codeforces 185E: Soap Time! - 2
884 Codeforces 185D: Visit of the Great
883 Codeforces 185C: Clever Fat Rat
882 Codeforces 185B: Mushroom Scientists
881 Codeforces 185A: Plant
880 Codeforces 183E: Candy Shop
879 Codeforces 183D: T-shirt
878 Codeforces 183C: Cyclic Coloring
877 Codeforces 183B: Zoo
876 Codeforces 183A: Headquarters
875 Codeforces 182E: Wooden Fence
874 Codeforces 182D: Common Divisors
873 Codeforces 182C: Optimal Sum
872 Codeforces 182B: Vasya's Calendar
871 Codeforces 182A: Battlefield
870 Codeforces 181B: Number of Triplets
869 Codeforces 181A: Series of Crimes
868 Codeforces 180F: Mathematical Analysis Rocks!
867 Codeforces 180E: Cubes
866 Codeforces 180D: Name
865 Codeforces 180C: Letter
864 Codeforces 180B: Divisibility Rules
863 Codeforces 180A: Defragmentation
862 Codeforces 178F3: Representative Sampling
861 Codeforces 178F2: Representative Sampling
860 Codeforces 178F1: Representative Sampling
859 Codeforces 178E3: The Beaver's Problem - 2
858 Codeforces 178E2: The Beaver's Problem - 2
857 Codeforces 178E1: The Beaver's Problem - 2
856 Codeforces 178D3: Magic Squares
855 Codeforces 178D2: Magic Squares
854 Codeforces 178D1: Magic Squares
853 Codeforces 178C3: Smart Beaver and Resolving Collisions
852 Codeforces 178C2: Smart Beaver and Resolving Collisions
851 Codeforces 178C1: Smart Beaver and Resolving Collisions
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