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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)
300 Codeforces 58A: Chat room
299 Codeforces 57E: Chess
298 Codeforces 57D: Journey
297 Codeforces 57C: Array
296 Codeforces 57B: Martian Architecture
295 Codeforces 57A: Square Earth?
294 Codeforces 56E: Domino Principle
293 Codeforces 56D: Changing a String
292 Codeforces 56C: Corporation Mail
291 Codeforces 56B: Spoilt Permutation
290 Codeforces 56A: Bar
289 Codeforces 55E: Very simple problem
288 Codeforces 55D: Beautiful numbers
287 Codeforces 55C: Pie or die
286 Codeforces 55B: Smallest number
285 Codeforces 55A: Flea travel
284 Codeforces 54E: Vacuum Сleaner
283 Codeforces 54D: Writing a Song
282 Codeforces 54C: First Digit Law
281 Codeforces 54B: Cutting Jigsaw Puzzle
280 Codeforces 54A: Presents
279 Codeforces 53E: Dead Ends
278 Codeforces 53D: Physical Education
277 Codeforces 53C: Little Frog
276 Codeforces 53B: Blog Photo
275 Codeforces 53A: Autocomplete
274 Codeforces 52C: Circular RMQ
273 Codeforces 52B: Right Triangles
272 Codeforces 52A: 123-sequence
271 Codeforces 51F: Caterpillar
270 Codeforces 51E: Pentagon
269 Codeforces 51D: Geometrical problem
268 Codeforces 51C: Three Base Stations
267 Codeforces 51B: bHTML Tables Analisys
266 Codeforces 51A: Cheaterius's Problem
265 Codeforces 50E: Square Equation Roots
264 Codeforces 50D: Bombing
263 Codeforces 50C: Happy Farm 5
262 Codeforces 50B: Choosing Symbol Pairs
261 Codeforces 50A: Domino piling
260 Codeforces 49E: Common ancestor
259 Codeforces 49D: Game
258 Codeforces 49C: Disposition
257 Codeforces 49B: Sum
256 Codeforces 49A: Sleuth
255 Codeforces 48H: Black and White
254 Codeforces 48G: Galaxy Union
253 Codeforces 48F: Snow sellers
252 Codeforces 48E: Ivan the Fool VS Gorynych the Dragon
251 Codeforces 48D: Permutations
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