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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)
8400 Codeforces 1783E: Game of the Year
8399 Codeforces 1783D: Different Arrays
8398 Codeforces 1783C: Yet Another Tournament
8397 Codeforces 1783B: Matrix of Differences
8396 Codeforces 1783A: Make it Beautiful
8395 Codeforces 1781H2: Window Signals (hard version)
8394 Codeforces 1781H1: Window Signals (easy version)
8393 Codeforces 1781G: Diverse Coloring
8392 Codeforces 1781F: Bracket Insertion
8391 Codeforces 1781E: Rectangle Shrinking
8390 Codeforces 1781D: Many Perfect Squares
8389 Codeforces 1781C: Equal Frequencies
8388 Codeforces 1781B: Going to the Cinema
8387 Codeforces 1781A: Parallel Projection
8386 Codeforces 1780G: Delicious Dessert
8385 Codeforces 1780F: Three Chairs
8384 Codeforces 1780E: Josuke and Complete Graph
8383 Codeforces 1780D: Bit Guessing Game
8382 Codeforces 1780B: GCD Partition
8381 Codeforces 1780A: Hayato and School
8380 Codeforces 1779H: Olympic Team Building
8379 Codeforces 1779G: The Game of the Century
8378 Codeforces 1779F: Xorcerer's Stones
8377 Codeforces 1779E: Anya's Simultaneous Exhibition
8376 Codeforces 1779D: Boris and His Amazing Haircut
8375 Codeforces 1779C: Least Prefix Sum
8374 Codeforces 1779B: MKnez's ConstructiveForces Task
8373 Codeforces 1779A: Hall of Fame
8372 Codeforces 1778F: Maximizing Root
8371 Codeforces 1778E: The Tree Has Fallen!
8370 Codeforces 1778D: Flexible String Revisit
8369 Codeforces 1778C: Flexible String
8368 Codeforces 1778B: The Forbidden Permutation
8367 Codeforces 1778A: Flip Flop Sum
8366 Codeforces 1777F: Comfortably Numb
8365 Codeforces 1777E: Edge Reverse
8364 Codeforces 1777D: Score of a Tree
8363 Codeforces 1777C: Quiz Master
8362 Codeforces 1777B: Emordnilap
8361 Codeforces 1777A: Everybody Likes Good Arrays!
8360 Codeforces 1776N: Count Permutations
8359 Codeforces 1776M: Parmigiana With Seafood
8358 Codeforces 1776L: Controllers
8357 Codeforces 1776K: Uniform Chemistry
8356 Codeforces 1776J: Italian Data Centers
8355 Codeforces 1776I: Spinach Pizza
8354 Codeforces 1776H: Beppa and SwerChat
8353 Codeforces 1776G: Another Wine Tasting Event
8352 Codeforces 1776F: Train Splitting
8351 Codeforces 1776E: Crossing the Railways
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