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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)
7350 Codeforces 1606E: Arena
7349 Codeforces 1606D: Red-Blue Matrix
7348 Codeforces 1606C: Banknotes
7347 Codeforces 1606B: Update Files
7346 Codeforces 1606A: AB Balance
7345 Codeforces 1605F: PalindORme
7344 Codeforces 1605E: Array Equalizer
7343 Codeforces 1605D: Treelabeling
7342 Codeforces 1605C: Dominant Character
7341 Codeforces 1605B: Reverse Sort
7340 Codeforces 1605A: A.M. Deviation
7339 Codeforces 1604B: XOR Specia-LIS-t
7338 Codeforces 1604A: Era
7337 Codeforces 1603F: October 18, 2017
7336 Codeforces 1603E: A Perfect Problem
7335 Codeforces 1603D: Artistic Partition
7334 Codeforces 1603C: Extreme Extension
7333 Codeforces 1603B: Moderate Modular Mode
7332 Codeforces 1603A: Di-visible Confusion
7331 Codeforces 1602B: Divine Array
7330 Codeforces 1602A: Two Subsequences
7329 Codeforces 1601F: Two Sorts
7328 Codeforces 1601E: Phys Ed Online
7327 Codeforces 1601D: Difficult Mountain
7326 Codeforces 1601C: Optimal Insertion
7325 Codeforces 1601B: Frog Traveler
7324 Codeforces 1601A: Array Elimination
7323 Codeforces 1600J: Robot Factory
7322 Codeforces 1600F: Party Organization
7321 Codeforces 1600E: Array Game
7320 Codeforces 1599J: Bob's Beautiful Array
7319 Codeforces 1599I: Desert
7318 Codeforces 1599H: Hidden Fortress
7317 Codeforces 1599G: Shortest path
7316 Codeforces 1599F: Mars
7315 Codeforces 1599E: Two Arrays
7314 Codeforces 1599D: Bubble Popping
7313 Codeforces 1599C: Bubble Strike
7312 Codeforces 1599B: Restaurant Game
7311 Codeforces 1599A: Weights
7310 Codeforces 1598G: The Sum of Good Numbers
7309 Codeforces 1598F: RBS
7308 Codeforces 1598E: Staircases
7307 Codeforces 1598D: Training Session
7306 Codeforces 1598C: Delete Two Elements
7305 Codeforces 1598B: Groups
7304 Codeforces 1598A: Computer Game
7303 Codeforces 1594F: Ideal Farm
7302 Codeforces 1594E2: Rubik's Cube Coloring (hard version)
7301 Codeforces 1594E1: Rubik's Cube Coloring (easy version)
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