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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)
8500 Codeforces 1800A: Is It a Cat?
8499 Codeforces 1799H: Tree Cutting
8498 Codeforces 1799G: Count Voting
8497 Codeforces 1799F: Halve or Subtract
8496 Codeforces 1799E: City Union
8495 Codeforces 1799D2: Hot Start Up (hard version)
8494 Codeforces 1799D1: Hot Start Up (easy version)
8493 Codeforces 1799C: Double Lexicographically Minimum
8492 Codeforces 1799B: Equalize by Divide
8491 Codeforces 1799A: Recent Actions
8490 Codeforces 1798F: Gifts from Grandfather Ahmed
8489 Codeforces 1798E: Multitest Generator
8488 Codeforces 1798D: Shocking Arrangement
8487 Codeforces 1798C: Candy Store
8486 Codeforces 1798B: Three Sevens
8485 Codeforces 1798A: Showstopper
8484 Codeforces 1797F: Li Hua and Path
8483 Codeforces 1797E: Li Hua and Array
8482 Codeforces 1797D: Li Hua and Tree
8481 Codeforces 1797C: Li Hua and Chess
8480 Codeforces 1797B: Li Hua and Pattern
8479 Codeforces 1797A: Li Hua and Maze
8478 Codeforces 1796F: Strange Triples
8477 Codeforces 1796E: Colored Subgraphs
8476 Codeforces 1796D: Maximum Subarray
8475 Codeforces 1796C: Maximum Set
8474 Codeforces 1796B: Asterisk-Minor Template
8473 Codeforces 1796A: Typical Interview Problem
8472 Codeforces 1795G: Removal Sequences
8471 Codeforces 1795F: Blocking Chips
8470 Codeforces 1795E: Explosions?
8469 Codeforces 1795D: Triangle Coloring
8468 Codeforces 1795C: Tea Tasting
8467 Codeforces 1795B: Ideal Point
8466 Codeforces 1795A: Two Towers
8465 Codeforces 1794E: Labeling the Tree with Distances
8464 Codeforces 1794D: Counting Factorizations
8463 Codeforces 1794C: Scoring Subsequences
8462 Codeforces 1794B: Not Dividing
8461 Codeforces 1794A: Prefix and Suffix Array
8460 Codeforces 1793F: Rebrending
8459 Codeforces 1793E: Velepin and Marketing
8458 Codeforces 1793D: Moscow Gorillas
8457 Codeforces 1793C: Dora and Search
8456 Codeforces 1793B: Fedya and Array
8455 Codeforces 1793A: Yet Another Promotion
8454 Codeforces 1792F2: Graph Coloring (hard version)
8453 Codeforces 1792F1: Graph Coloring (easy version)
8452 Codeforces 1792E: Divisors and Table
8451 Codeforces 1792D: Fixed Prefix Permutations
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