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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)
24335 Codeforces 1896C: Matching Arrays
24334 Codeforces 1896B: AB Flipping
24333 Codeforces 1896A: Jagged Swaps
24332 Codeforces 1895G: Two Characters, Two Colors
24331 Codeforces 1895F: Fancy Arrays
24330 Codeforces 1895E: Infinite Card Game
24329 Codeforces 1895D: XOR Construction
24328 Codeforces 1895C: Torn Lucky Ticket
24327 Codeforces 1895B: Points and Minimum Distance
24326 Codeforces 1895A: Treasure Chest
24325 Codeforces 1894B: Two Out of Three
24324 Codeforces 1894A: Secret Sport
24323 Codeforces 1893E: Cacti Symphony
24322 Codeforces 1893D: Colorful Constructive
24321 Codeforces 1893C: Freedom of Choice
24320 Codeforces 1893B: Neutral Tonality
24319 Codeforces 1893A: Anonymous Informant
24318 Codeforces 1891F: A Growing Tree
24317 Codeforces 1891E: Brukhovich and Exams
24316 Codeforces 1891D: Suspicious logarithms
24315 Codeforces 1891C: Smilo and Monsters
24314 Codeforces 1891B: Deja Vu
24313 Codeforces 1891A: Sorting with Twos
24312 Codeforces 1885A: Deterministic Scheduling for Extended Reality over 5G and Beyond
24311 Codeforces 649E: Автобус
24310 Codeforces 649D: Дефрагментация памяти
24309 Codeforces 649C: Печать условий
24308 Codeforces 649B: Этажи
24307 Codeforces 649A: Любимые числа Поликарпа
24306 Codeforces 648E: Собери число
24305 Codeforces 648D: Собачки и миски
24304 Codeforces 648C: Путь Робота
24303 Codeforces 648B: Собери стол
24302 Codeforces 648A: Наибольший подъем
24144 Codeforces 1890B: Qingshan Loves Strings
24143 Codeforces 1890A: Doremy's Paint 3
24142 Codeforces 1889F: Doremy's Average Tree
24141 Codeforces 1889E: Doremy's Swapping Trees
24140 Codeforces 1889D: Game of Stacks
24139 Codeforces 1889C2: Doremy's Drying Plan (Hard Version)
24138 Codeforces 1889C1: Doremy's Drying Plan (Easy Version)
24137 Codeforces 1889B: Doremy's Connecting Plan
24136 Codeforces 1889A: Qingshan Loves Strings 2
24075 Codeforces 1887F: Minimum Segments
24074 Codeforces 1887E: Good Colorings
24073 Codeforces 1887D: Split
24072 Codeforces 1887C: Minimum Array
24071 Codeforces 1887B: Time Travel
24070 Codeforces 1886F: Diamond Theft
24069 Codeforces 1886E: I Wanna be the Team Leader
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