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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)
550 Codeforces 113A: Grammar Lessons
549 Codeforces 112B: Petya and Square
548 Codeforces 112A: Petya and Strings
547 Codeforces 111E: Petya and Rectangle
546 Codeforces 111D: Petya and Coloring
545 Codeforces 111C: Petya and Spiders
544 Codeforces 111B: Petya and Divisors
543 Codeforces 111A: Petya and Inequiations
542 Codeforces 110B: Lucky String
541 Codeforces 110A: Nearly Lucky Number
540 Codeforces 109E: Lucky Interval
539 Codeforces 109D: Lucky Sorting
538 Codeforces 109C: Lucky Tree
537 Codeforces 109B: Lucky Probability
536 Codeforces 109A: Lucky Sum of Digits
535 Codeforces 108B: Datatypes
534 Codeforces 108A: Palindromic Times
533 Codeforces 107E: Darts
532 Codeforces 107D: Crime Management
531 Codeforces 107C: Arrangement
530 Codeforces 107B: Basketball Team
529 Codeforces 107A: Dorm Water Supply
528 Codeforces 106E: Space Rescuers
527 Codeforces 106D: Treasure Island
526 Codeforces 106C: Buns
525 Codeforces 106B: Choosing Laptop
524 Codeforces 106A: Card Game
523 Codeforces 105E: Lift and Throw
522 Codeforces 105D: Entertaining Geodetics
521 Codeforces 105C: Item World
520 Codeforces 105B: Dark Assembly
519 Codeforces 105A: Transmigration
518 Codeforces 104A: Blackjack
517 Codeforces 103E: Buying Sets
516 Codeforces 103D: Time to Raid Cowavans
515 Codeforces 103C: Russian Roulette
514 Codeforces 103B: Cthulhu
513 Codeforces 103A: Testing Pants for Sadness
512 Codeforces 102B: Sum of Digits
511 Codeforces 102A: Clothes
510 Codeforces 101E: Candies and Stones
509 Codeforces 101D: Castle
508 Codeforces 101C: Vectors
507 Codeforces 101B: Buses
506 Codeforces 101A: Homework
505 Codeforces 100J: Interval Coloring
504 Codeforces 100I: Rotation
503 Codeforces 100H: Battleship
502 Codeforces 100G: Name the album
501 Codeforces 100F: Polynom
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