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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)
24505 Codeforces 1922A: Tricky Template
24504 Codeforces 1921G: Mischievous Shooter
24503 Codeforces 1921F: Sum of Progression
24502 Codeforces 1921E: Eat the Chip
24501 Codeforces 1921D: Very Different Array
24500 Codeforces 1921C: Sending Messages
24499 Codeforces 1921B: Arranging Cats
24498 Codeforces 1921A: Square
24497 Codeforces 1920F2: Smooth Sailing (Hard Version)
24496 Codeforces 1920F1: Smooth Sailing (Easy Version)
24495 Codeforces 1920E: Counting Binary Strings
24494 Codeforces 1920D: Array Repetition
24493 Codeforces 1920C: Partitioning the Array
24492 Codeforces 1920B: Summation Game
24491 Codeforces 1920A: Satisfying Constraints
24490 Codeforces 1919H: Tree Diameter
24489 Codeforces 1919G: Tree LGM
24488 Codeforces 1919F2: Wine Factory (Hard Version)
24487 Codeforces 1919F1: Wine Factory (Easy Version)
24486 Codeforces 1919E: Counting Prefixes
24485 Codeforces 1919D: 01 Tree
24484 Codeforces 1919C: Grouping Increases
24483 Codeforces 1919B: Plus-Minus Split
24482 Codeforces 1919A: Wallet Exchange
24481 Codeforces 1917F: Construct Tree
24480 Codeforces 1917E: Construct Matrix
24479 Codeforces 1917D: Yet Another Inversions Problem
24478 Codeforces 1917C: Watering an Array
24477 Codeforces 1917B: Erase First or Second Letter
24476 Codeforces 1917A: Least Product
24475 Codeforces 1916H2: Matrix Rank (Hard Version)
24474 Codeforces 1916H1: Matrix Rank (Easy Version)
24473 Codeforces 1916G: Optimizations From Chelsu
24472 Codeforces 1916F: Group Division
24471 Codeforces 1916E: Happy Life in University
24470 Codeforces 1916D: Mathematical Problem
24469 Codeforces 1916C: Training Before the Olympiad
24468 Codeforces 1916B: Two Divisors
24467 Codeforces 1916A: 2023
24466 Codeforces 1915G: Bicycles
24465 Codeforces 1915F: Greetings
24464 Codeforces 1915E: Romantic Glasses
24463 Codeforces 1915D: Unnatural Language Processing
24462 Codeforces 1915C: Can I Square?
24461 Codeforces 1915B: Not Quite Latin Square
24460 Codeforces 1915A: Odd One Out
24459 Codeforces 1914G2: Light Bulbs (Hard Version)
24458 Codeforces 1914G1: Light Bulbs (Easy Version)
24457 Codeforces 1914F: Programming Competition
24456 Codeforces 1914E2: Game with Marbles (Hard Version)
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