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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
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ID Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)
6150 Codeforces 1369C: RationalLee
6149 Codeforces 1369B: AccurateLee
6148 Codeforces 1369A: FashionabLee
6147 Codeforces 1368H2: Breadboard Capacity (hard version)
6146 Codeforces 1368H1: Breadboard Capacity (easy version)
6145 Codeforces 1368G: Shifting Dominoes
6144 Codeforces 1368F: Lamps on a Circle
6143 Codeforces 1368E: Ski Accidents
6142 Codeforces 1368D: AND, OR and square sum
6141 Codeforces 1368C: Even Picture
6140 Codeforces 1368B: Codeforces Subsequences
6139 Codeforces 1368A: C+=
6138 Codeforces 1367F2: Flying Sort (Hard Version)
6137 Codeforces 1367F1: Flying Sort (Easy Version)
6136 Codeforces 1367E: Necklace Assembly
6135 Codeforces 1367D: Task On The Board
6134 Codeforces 1367C: Social Distance
6133 Codeforces 1367B: Even Array
6132 Codeforces 1367A: Short Substrings
6131 Codeforces 1366G: Construct the String
6130 Codeforces 1366F: Jog Around The Graph
6129 Codeforces 1366E: Two Arrays
6128 Codeforces 1366D: Two Divisors
6127 Codeforces 1366C: Palindromic Paths
6126 Codeforces 1366B: Shuffle
6125 Codeforces 1366A: Shovels and Swords
6124 Codeforces 1365G: Secure Password
6123 Codeforces 1365F: Swaps Again
6122 Codeforces 1365E: Maximum Subsequence Value
6121 Codeforces 1365D: Solve The Maze
6120 Codeforces 1365C: Rotation Matching
6119 Codeforces 1365B: Trouble Sort
6118 Codeforces 1365A: Matrix Game
6117 Codeforces 1364E: X-OR
6116 Codeforces 1364D: Ehab's Last Corollary
6115 Codeforces 1364C: Ehab and Prefix MEXs
6114 Codeforces 1364B: Most socially-distanced subsequence
6113 Codeforces 1364A: XXXXX
6112 Codeforces 1363F: Rotating Substrings
6111 Codeforces 1363E: Tree Shuffling
6110 Codeforces 1363D: Guess The Maximums
6109 Codeforces 1363C: Game On Leaves
6108 Codeforces 1363B: Subsequence Hate
6107 Codeforces 1363A: Odd Selection
6106 Codeforces 1362C: Johnny and Another Rating Drop
6105 Codeforces 1362B: Johnny and His Hobbies
6104 Codeforces 1362A: Johnny and Ancient Computer
6103 Codeforces 1361F: Johnny and New Toy
6102 Codeforces 1361E: James and the Chase
6101 Codeforces 1361D: Johnny and James
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