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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)
5500 Codeforces 1244G: Running in Pairs
5499 Codeforces 1244F: Chips
5498 Codeforces 1244E: Minimizing Difference
5497 Codeforces 1244D: Paint the Tree
5496 Codeforces 1244C: The Football Season
5495 Codeforces 1244B: Rooms and Staircases
5494 Codeforces 1244A: Pens and Pencils
5493 Codeforces 1243B2: Character Swap (Hard Version)
5492 Codeforces 1243B1: Character Swap (Easy Version)
5491 Codeforces 1243A: Maximum Square
5490 Codeforces 1242E: Planar Perimeter
5489 Codeforces 1242D: Number Discovery
5488 Codeforces 1242C: Sum Balance
5487 Codeforces 1242B: 0-1 MST
5486 Codeforces 1242A: Tile Painting
5485 Codeforces 1240F: Football
5484 Codeforces 1239F: Swiper, no swiping!
5483 Codeforces 1239E: Turtle
5482 Codeforces 1239D: Catowice City
5481 Codeforces 1239C: Queue in the Train
5480 Codeforces 1239B: The World Is Just a Programming Task (Hard Version)
5479 Codeforces 1239A: Ivan the Fool and the Probability Theory
5478 Codeforces 1238G: Adilbek and the Watering System
5477 Codeforces 1238F: The Maximum Subtree
5476 Codeforces 1238E: Keyboard Purchase
5475 Codeforces 1238D: AB-string
5474 Codeforces 1238C: Standard Free2play
5473 Codeforces 1238B: Kill `Em All
5472 Codeforces 1238A: Prime Subtraction
5471 Codeforces 1237H: Balanced Reversals
5470 Codeforces 1237G: Balanced Distribution
5469 Codeforces 1237F: Balanced Domino Placements
5468 Codeforces 1237E: Balanced Binary Search Trees
5467 Codeforces 1237D: Balanced Playlist
5466 Codeforces 1237C2: Balanced Removals (Harder)
5465 Codeforces 1237C1: Balanced Removals (Easier)
5464 Codeforces 1237B: Balanced Tunnel
5463 Codeforces 1237A: Balanced Rating Changes
5462 Codeforces 1236F: Alice and the Cactus
5461 Codeforces 1236E: Alice and the Unfair Game
5460 Codeforces 1236D: Alice and the Doll
5459 Codeforces 1236C: Labs
5458 Codeforces 1236B: Alice and the List of Presents
5457 Codeforces 1236A: Stones
5456 Codeforces 1234F: Yet Another Substring Reverse
5455 Codeforces 1234E: Special Permutations
5454 Codeforces 1234D: Distinct Characters Queries
5453 Codeforces 1234C: Pipes
5452 Codeforces 1234B2: Social Network (hard version)
5451 Codeforces 1234B1: Social Network (easy version)
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