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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)
6400 Codeforces 1420E: Battle Lemmings
6399 Codeforces 1420D: Rescue Nibel!
6398 Codeforces 1420C2: Pokémon Army (hard version)
6397 Codeforces 1420C1: Pokémon Army (easy version)
6396 Codeforces 1420B: Rock and Lever
6395 Codeforces 1420A: Cubes Sorting
6394 Codeforces 1419F: Rain of Fire
6393 Codeforces 1419E: Decryption
6392 Codeforces 1419D2: Sage's Birthday (hard version)
6391 Codeforces 1419D1: Sage's Birthday (easy version)
6390 Codeforces 1419C: Killjoy
6389 Codeforces 1419B: Stairs
6388 Codeforces 1419A: Digit Game
6387 Codeforces 1418G: Three Occurrences
6386 Codeforces 1418F: Equal Product
6385 Codeforces 1418E: Expected Damage
6384 Codeforces 1418D: Trash Problem
6383 Codeforces 1418C: Mortal Kombat Tower
6382 Codeforces 1418B: Negative Prefixes
6381 Codeforces 1418A: Buying Torches
6380 Codeforces 1417B: Two Arrays
6379 Codeforces 1417A: Copy-paste
6378 Codeforces 1416F: Showing Off
6377 Codeforces 1416E: Split
6376 Codeforces 1416D: Graph and Queries
6375 Codeforces 1416C: XOR Inverse
6374 Codeforces 1416B: Make Them Equal
6373 Codeforces 1416A: k-Amazing Numbers
6372 Codeforces 1415F: Cakes for Clones
6371 Codeforces 1415E: New Game Plus!
6370 Codeforces 1415D: XOR-gun
6369 Codeforces 1415C: Bouncing Ball
6368 Codeforces 1415B: Repainting Street
6367 Codeforces 1415A: Prison Break
6366 Codeforces 1413F: Roads and Ramen
6365 Codeforces 1413E: Solo mid Oracle
6364 Codeforces 1413D: Shurikens
6363 Codeforces 1413C: Perform Easily
6362 Codeforces 1413B: A New Technique
6361 Codeforces 1413A: Finding Sasuke
6360 Codeforces 1411G: No Game No Life
6359 Codeforces 1411F: The Thorny Path
6358 Codeforces 1411E: Poman Numbers
6357 Codeforces 1411D: Grime Zoo
6356 Codeforces 1411C: Peaceful Rooks
6355 Codeforces 1411B: Fair Numbers
6354 Codeforces 1411A: In-game Chat
6353 Codeforces 1409F: Subsequences of Length Two
6352 Codeforces 1409E: Two Platforms
6351 Codeforces 1409D: Decrease the Sum of Digits
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