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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)
600 Codeforces 123E: Maze
599 Codeforces 123D: String
598 Codeforces 123C: Brackets
597 Codeforces 123B: Squares
596 Codeforces 123A: Prime Permutation
595 Codeforces 122B: Lucky Substring
594 Codeforces 122A: Lucky Division
593 Codeforces 121E: Lucky Array
592 Codeforces 121D: Lucky Segments
591 Codeforces 121C: Lucky Permutation
590 Codeforces 121B: Lucky Transformation
589 Codeforces 121A: Lucky Sum
588 Codeforces 120J: Minimum Sum
587 Codeforces 120I: Luck is in Numbers
586 Codeforces 120H: Brevity is Soul of Wit
585 Codeforces 120G: Boom
584 Codeforces 120F: Spiders
583 Codeforces 120E: Put Knight!
582 Codeforces 120D: Three Sons
581 Codeforces 120C: Winnie-the-Pooh and honey
580 Codeforces 120B: Quiz League
579 Codeforces 120A: Elevator
578 Codeforces 119E: Alternative Reality
577 Codeforces 119D: String Transformation
576 Codeforces 119C: Education Reform
575 Codeforces 119B: Before Exam
574 Codeforces 119A: Epic Game
573 Codeforces 118E: Bertown roads
572 Codeforces 118D: Caesar's Legions
571 Codeforces 118C: Fancy Number
570 Codeforces 118B: Present from Lena
569 Codeforces 118A: String Task
568 Codeforces 117E: Tree or not Tree
567 Codeforces 117D: Not Quick Transformation
566 Codeforces 117C: Cycle
565 Codeforces 117B: Very Interesting Game
564 Codeforces 117A: Elevator
563 Codeforces 116B: Little Pigs and Wolves
562 Codeforces 116A: Tram
561 Codeforces 115E: Linear Kingdom Races
560 Codeforces 115D: Unambiguous Arithmetic Expression
559 Codeforces 115C: Plumber
558 Codeforces 115B: Lawnmower
557 Codeforces 115A: Party
556 Codeforces 114B: PFAST Inc.
555 Codeforces 114A: Cifera
554 Codeforces 113E: Sleeping
553 Codeforces 113D: Museum
552 Codeforces 113C: Double Happiness
551 Codeforces 113B: Petr#
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