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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)
4400 Codeforces 1027B: Numbers on the Chessboard
4399 Codeforces 1027A: Palindromic Twist
4398 Codeforces 1025G: Company Acquisitions
4397 Codeforces 1025F: Disjoint Triangles
4396 Codeforces 1025E: Colored Cubes
4395 Codeforces 1025D: Recovering BST
4394 Codeforces 1025C: Plasticine zebra
4393 Codeforces 1025B: Weakened Common Divisor
4392 Codeforces 1025A: Doggo Recoloring
4391 Codeforces 1023G: Pisces
4390 Codeforces 1023F: Mobile Phone Network
4389 Codeforces 1023E: Down or Right
4388 Codeforces 1023D: Array Restoration
4387 Codeforces 1023C: Bracket Subsequence
4386 Codeforces 1023B: Pair of Toys
4385 Codeforces 1023A: Single Wildcard Pattern Matching
4384 Codeforces 1020B: Badge
4383 Codeforces 1020A: New Building for SIS
4382 Codeforces 1019E: Raining season
4381 Codeforces 1019D: Large Triangle
4380 Codeforces 1019C: Sergey's problem
4379 Codeforces 1019B: The hat
4378 Codeforces 1019A: Elections
4377 Codeforces 1017H: The Films
4376 Codeforces 1017G: The Tree
4375 Codeforces 1017F: The Neutral Zone
4374 Codeforces 1017E: The Supersonic Rocket
4373 Codeforces 1017D: The Wu
4372 Codeforces 1017C: The Phone Number
4371 Codeforces 1017B: The Bits
4370 Codeforces 1017A: The Rank
4369 Codeforces 1016G: Appropriate Team
4368 Codeforces 1016F: Road Projects
4367 Codeforces 1016E: Rest In The Shades
4366 Codeforces 1016D: Vasya And The Matrix
4365 Codeforces 1016C: Vasya And The Mushrooms
4364 Codeforces 1016B: Segment Occurrences
4363 Codeforces 1016A: Death Note
4362 Codeforces 1015F: Bracket Substring
4361 Codeforces 1015E2: Stars Drawing (Hard Edition)
4360 Codeforces 1015E1: Stars Drawing (Easy Edition)
4359 Codeforces 1015D: Walking Between Houses
4358 Codeforces 1015C: Songs Compression
4357 Codeforces 1015B: Obtaining the String
4356 Codeforces 1015A: Points in Segments
4355 Codeforces 1013B: And
4354 Codeforces 1013A: Piles With Stones
4353 Codeforces 1012F: Passports
4352 Codeforces 1012E: Cycle sort
4351 Codeforces 1012D: AB-Strings
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