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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)
5305 Codeforces 1204E: Natasha, Sasha and the Prefix Sums
5304 Codeforces 1204D2: Kirk and a Binary String (hard version)
5303 Codeforces 1204D1: Kirk and a Binary String (easy version)
5302 Codeforces 1204C: Anna, Svyatoslav and Maps
5301 Codeforces 1204B: Mislove Has Lost an Array
5300 Codeforces 1204A: BowWow and the Timetable
5299 Codeforces 1203F2: Complete the Projects (hard version)
5298 Codeforces 1203F1: Complete the Projects (easy version)
5297 Codeforces 1203E: Boxers
5296 Codeforces 1203D2: Remove the Substring (hard version)
5295 Codeforces 1203D1: Remove the Substring (easy version)
5294 Codeforces 1203C: Common Divisors
5293 Codeforces 1203B: Equal Rectangles
5292 Codeforces 1203A: Circle of Students
5291 Codeforces 1202F: You Are Given Some Letters...
5290 Codeforces 1202E: You Are Given Some Strings...
5289 Codeforces 1202D: Print a 1337-string...
5288 Codeforces 1202C: You Are Given a WASD-string...
5287 Codeforces 1202B: You Are Given a Decimal String...
5286 Codeforces 1202A: You Are Given Two Binary Strings...
5285 Codeforces 1201E2: Knightmare (hard)
5284 Codeforces 1201E1: Knightmare (easy)
5283 Codeforces 1201D: Treasure Hunting
5282 Codeforces 1201C: Maximum Median
5281 Codeforces 1201B: Zero Array
5280 Codeforces 1201A: Important Exam
5279 Codeforces 1200F: Graph Traveler
5278 Codeforces 1200E: Compress Words
5277 Codeforces 1200D: White Lines
5276 Codeforces 1200C: Round Corridor
5275 Codeforces 1200B: Block Adventure
5274 Codeforces 1200A: Hotelier
5273 Codeforces 1199B: Water Lily
5272 Codeforces 1199A: City Day
5271 Codeforces 1198F: GCD Groups 2
5270 Codeforces 1198E: Rectangle Painting 2
5269 Codeforces 1198D: Rectangle Painting 1
5268 Codeforces 1198C: Matching vs Independent Set
5267 Codeforces 1198B: Welfare State
5266 Codeforces 1198A: MP3
5265 Codeforces 1197F: Coloring Game
5264 Codeforces 1197E: Culture Code
5263 Codeforces 1197D: Yet Another Subarray Problem
5262 Codeforces 1197C: Array Splitting
5261 Codeforces 1197B: Pillars
5260 Codeforces 1197A: DIY Wooden Ladder
5259 Codeforces 1196F: K-th Path
5258 Codeforces 1196E: Connected Component on a Chessboard
5257 Codeforces 1196D2: RGB Substring (hard version)
5256 Codeforces 1196D1: RGB Substring (easy version)
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