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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)
4900 Codeforces 1129B: Wrong Answer
4899 Codeforces 1129A2: Toy Train
4898 Codeforces 1129A1: Toy Train (Simplified)
4897 Codeforces 1121C: System Testing
4896 Codeforces 1121B: Mike and Children
4895 Codeforces 1121A: Technogoblet of Fire
4894 Codeforces 1120F: Secret Letters
4893 Codeforces 1120E: The very same Munchhausen
4892 Codeforces 1120D: Power Tree
4891 Codeforces 1120C: Compress String
4890 Codeforces 1120B: Once in a casino
4889 Codeforces 1120A: Diana and Liana
4888 Codeforces 1119H: Triple
4887 Codeforces 1119G: Get Ready for the Battle
4886 Codeforces 1119F: Niyaz and Small Degrees
4885 Codeforces 1119E: Pavel and Triangles
4884 Codeforces 1119D: Frets On Fire
4883 Codeforces 1119C: Ramesses and Corner Inversion
4882 Codeforces 1119B: Alyona and a Narrow Fridge
4881 Codeforces 1119A: Ilya and a Colorful Walk
4880 Codeforces 1118F2: Tree Cutting (Hard Version)
4879 Codeforces 1118F1: Tree Cutting (Easy Version)
4878 Codeforces 1118E: Yet Another Ball Problem
4877 Codeforces 1118D2: Coffee and Coursework (Hard Version)
4876 Codeforces 1118D1: Coffee and Coursework (Easy version)
4875 Codeforces 1118C: Palindromic Matrix
4874 Codeforces 1118B: Tanya and Candies
4873 Codeforces 1118A: Water Buying
4872 Codeforces 1117G: Recursive Queries
4871 Codeforces 1117F: Crisp String
4870 Codeforces 1117E: Decypher the String
4869 Codeforces 1117D: Magic Gems
4868 Codeforces 1117C: Magic Ship
4867 Codeforces 1117B: Emotes
4866 Codeforces 1117A: Best Subsegment
4865 Codeforces 1116D6: Hessenberg matrix
4864 Codeforces 1116D5: Creeper
4863 Codeforces 1116D4: TIE fighter
4862 Codeforces 1116D3: X-wing fighter
4861 Codeforces 1116D2: Pattern of increasing blocks
4860 Codeforces 1116D1: Block diagonal matrix
4859 Codeforces 1116C3: ``Is the number of ones divisible by 3?'' oracle
4858 Codeforces 1116C2: ``Is the bit string periodic?'' oracle
4857 Codeforces 1116C1: Alternating bits oracle
4856 Codeforces 1116B2: Not A, not B or not C?
4855 Codeforces 1116B1: Distinguish three-qubit states
4854 Codeforces 1116A2: Generate equal superposition of four basis states
4853 Codeforces 1116A1: Generate state |00⟩ + |01⟩ + |10⟩
4852 Codeforces 1115U3: Block unitary
4851 Codeforces 1115U2: Chessboard unitary
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