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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)
7800 Codeforces 1682E: Unordered Swaps
7799 Codeforces 1682D: Circular Spanning Tree
7798 Codeforces 1682C: LIS or Reverse LIS?
7797 Codeforces 1682B: AND Sorting
7796 Codeforces 1682A: Palindromic Indices
7795 Codeforces 1681F: Unique Occurrences
7794 Codeforces 1681E: Labyrinth Adventures
7793 Codeforces 1681D: Required Length
7792 Codeforces 1681C: Double Sort
7791 Codeforces 1681B: Card Trick
7790 Codeforces 1681A: Game with Cards
7789 Codeforces 1680F: Lenient Vertex Cover
7788 Codeforces 1680E: Moving Chips
7787 Codeforces 1680D: Dog Walking
7786 Codeforces 1680C: Binary String
7785 Codeforces 1680B: Robots
7784 Codeforces 1680A: Minimums and Maximums
7783 Codeforces 1679F: Formalism for Formalism
7782 Codeforces 1679E: Typical Party in Dorm
7781 Codeforces 1679D: Toss a Coin to Your Graph...
7780 Codeforces 1679C: Rooks Defenders
7779 Codeforces 1679B: Stone Age Problem
7778 Codeforces 1679A: AvtoBus
7777 Codeforces 1678B2: Tokitsukaze and Good 01-String (hard version)
7776 Codeforces 1678B1: Tokitsukaze and Good 01-String (easy version)
7775 Codeforces 1678A: Tokitsukaze and All Zero Sequence
7774 Codeforces 1677F: Tokitsukaze and Gems
7773 Codeforces 1677E: Tokitsukaze and Beautiful Subsegments
7772 Codeforces 1677D: Tokitsukaze and Permutations
7771 Codeforces 1677C: Tokitsukaze and Two Colorful Tapes
7770 Codeforces 1677B: Tokitsukaze and Meeting
7769 Codeforces 1677A: Tokitsukaze and Strange Inequality
7768 Codeforces 1676H2: Maximum Crossings (Hard Version)
7767 Codeforces 1676H1: Maximum Crossings (Easy Version)
7766 Codeforces 1676G: White-Black Balanced Subtrees
7765 Codeforces 1676F: Longest Strike
7764 Codeforces 1676E: Eating Queries
7763 Codeforces 1676D: X-Sum
7762 Codeforces 1676C: Most Similar Words
7761 Codeforces 1676B: Equal Candies
7760 Codeforces 1676A: Lucky?
7759 Codeforces 1675G: Sorting Pancakes
7758 Codeforces 1675F: Vlad and Unfinished Business
7757 Codeforces 1675E: Replace With the Previous, Minimize
7756 Codeforces 1675D: Vertical Paths
7755 Codeforces 1675C: Detective Task
7754 Codeforces 1675B: Make It Increasing
7753 Codeforces 1675A: Food for Animals
7752 Codeforces 1674G: Remove Directed Edges
7751 Codeforces 1674F: Desktop Rearrangement
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