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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)
5400 Codeforces 1219C: Periodic integer number
5399 Codeforces 1218I: The Light Square
5398 Codeforces 1218H: Function Composition
5397 Codeforces 1218G: Alpha planetary system
5396 Codeforces 1218F: Workout plan
5395 Codeforces 1218E: Product Tuples
5394 Codeforces 1218D: Xor Spanning Tree
5393 Codeforces 1218C: Jumping Transformers
5392 Codeforces 1218B: Guarding warehouses
5391 Codeforces 1218A: BubbleReactor
5390 Codeforces 1217F: Forced Online Queries Problem
5389 Codeforces 1217E: Sum Queries?
5388 Codeforces 1217D: Coloring Edges
5387 Codeforces 1217C: The Number Of Good Substrings
5386 Codeforces 1217B: Zmei Gorynich
5385 Codeforces 1217A: Creating a Character
5384 Codeforces 1216F: Wi-Fi
5383 Codeforces 1216E2: Numerical Sequence (hard version)
5382 Codeforces 1216E1: Numerical Sequence (easy version)
5381 Codeforces 1216D: Swords
5380 Codeforces 1216C: White Sheet
5379 Codeforces 1216B: Shooting
5378 Codeforces 1216A: Prefixes
5377 Codeforces 1215F: Radio Stations
5376 Codeforces 1215E: Marbles
5375 Codeforces 1215D: Ticket Game
5374 Codeforces 1215C: Swap Letters
5373 Codeforces 1215B: The Number of Products
5372 Codeforces 1215A: Yellow Cards
5371 Codeforces 1214H: Tiles Placement
5370 Codeforces 1214G: Feeling Good
5369 Codeforces 1214F: Employment
5368 Codeforces 1214E: Petya and Construction Set
5367 Codeforces 1214D: Treasure Island
5366 Codeforces 1214C: Bad Sequence
5365 Codeforces 1214B: Badges
5364 Codeforces 1214A: Optimal Currency Exchange
5363 Codeforces 1213G: Path Queries
5362 Codeforces 1213F: Unstable String Sort
5361 Codeforces 1213E: Two Small Strings
5360 Codeforces 1213D2: Equalizing by Division (hard version)
5359 Codeforces 1213D1: Equalizing by Division (easy version)
5358 Codeforces 1213C: Book Reading
5357 Codeforces 1213B: Bad Prices
5356 Codeforces 1213A: Chips Moving
5355 Codeforces 1211I: Unusual Graph
5354 Codeforces 1211H: Road Repair in Treeland
5353 Codeforces 1211G: King's Path
5352 Codeforces 1211F: kotlinkotlinkotlinkotlin...
5351 Codeforces 1211E: Double Permutation Inc.
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