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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)
5050 Codeforces 1156F: Card Bag
5049 Codeforces 1156E: Special Segments of Permutation
5048 Codeforces 1156D: 0-1-Tree
5047 Codeforces 1156C: Match Points
5046 Codeforces 1156B: Ugly Pairs
5045 Codeforces 1156A: Inscribed Figures
5044 Codeforces 1155F: Delivery Oligopoly
5043 Codeforces 1155E: Guess the Root
5042 Codeforces 1155D: Beautiful Array
5041 Codeforces 1155C: Alarm Clocks Everywhere
5040 Codeforces 1155B: Game with Telephone Numbers
5039 Codeforces 1155A: Reverse a Substring
5038 Codeforces 1154G: Minimum Possible LCM
5037 Codeforces 1154F: Shovels Shop
5036 Codeforces 1154E: Two Teams
5035 Codeforces 1154D: Walking Robot
5034 Codeforces 1154C: Gourmet Cat
5033 Codeforces 1154B: Make Them Equal
5032 Codeforces 1154A: Restoring Three Numbers
5031 Codeforces 1153F: Serval and Bonus Problem
5030 Codeforces 1153E: Serval and Snake
5029 Codeforces 1153D: Serval and Rooted Tree
5028 Codeforces 1153C: Serval and Parenthesis Sequence
5027 Codeforces 1153B: Serval and Toy Bricks
5026 Codeforces 1153A: Serval and Bus
5025 Codeforces 1152F2: Neko Rules the Catniverse (Large Version)
5024 Codeforces 1152F1: Neko Rules the Catniverse (Small Version)
5023 Codeforces 1152E: Neko and Flashback
5022 Codeforces 1152D: Neko and Aki's Prank
5021 Codeforces 1152C: Neko does Maths
5020 Codeforces 1152B: Neko Performs Cat Furrier Transform
5019 Codeforces 1152A: Neko Finds Grapes
5018 Codeforces 1151F: Sonya and Informatics
5017 Codeforces 1151E: Number of Components
5016 Codeforces 1151D: Stas and the Queue at the Buffet
5015 Codeforces 1151C: Problem for Nazar
5014 Codeforces 1151B: Dima and a Bad XOR
5013 Codeforces 1151A: Maxim and Biology
5012 Codeforces 1150B: Tiling Challenge
5011 Codeforces 1150A: Stock Arbitraging
5010 Codeforces 1149E: Election Promises
5009 Codeforces 1149D: Abandoning Roads
5008 Codeforces 1149C: Tree Generator™
5007 Codeforces 1149B: Three Religions
5006 Codeforces 1149A: Prefix Sum Primes
5005 Codeforces 1148H: Holy Diver
5004 Codeforces 1148G: Gold Experience
5003 Codeforces 1148F: Foo Fighters
5002 Codeforces 1148E: Earth Wind and Fire
5001 Codeforces 1148D: Dirty Deeds Done Dirt Cheap
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