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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)
6600 Codeforces 1462E2: Close Tuples (hard version)
6599 Codeforces 1462E1: Close Tuples (easy version)
6598 Codeforces 1462D: Add to Neighbour and Remove
6597 Codeforces 1462C: Unique Number
6596 Codeforces 1462B: Last Year's Substring
6595 Codeforces 1462A: Favorite Sequence
6594 Codeforces 1461F: Mathematical Expression
6593 Codeforces 1461E: Water Level
6592 Codeforces 1461D: Divide and Summarize
6591 Codeforces 1461C: Random Events
6590 Codeforces 1461B: Find the Spruce
6589 Codeforces 1461A: String Generation
6588 Codeforces 1459B: Move and Turn
6587 Codeforces 1459A: Red-Blue Shuffle
6586 Codeforces 1458F: Range Diameter Sum
6585 Codeforces 1458E: Nim Shortcuts
6584 Codeforces 1458D: Flip and Reverse
6583 Codeforces 1458C: Latin Square
6582 Codeforces 1458B: Glass Half Spilled
6581 Codeforces 1458A: Row GCD
6580 Codeforces 1456E: XOR-ranges
6579 Codeforces 1455G: Forbidden Value
6578 Codeforces 1455F: String and Operations
6577 Codeforces 1455E: Four Points
6576 Codeforces 1455D: Sequence and Swaps
6575 Codeforces 1455C: Ping-pong
6574 Codeforces 1455B: Jumps
6573 Codeforces 1455A: Strange Functions
6572 Codeforces 1454F: Array Partition
6571 Codeforces 1454E: Number of Simple Paths
6570 Codeforces 1454D: Number into Sequence
6569 Codeforces 1454C: Sequence Transformation
6568 Codeforces 1454B: Unique Bid Auction
6567 Codeforces 1454A: Special Permutation
6566 Codeforces 1453F: Even Harder
6565 Codeforces 1453E: Dog Snacks
6564 Codeforces 1453D: Checkpoints
6563 Codeforces 1453C: Triangles
6562 Codeforces 1453B: Suffix Operations
6561 Codeforces 1453A: Cancel the Trains
6560 Codeforces 1452G: Game On Tree
6559 Codeforces 1452F: Divide Powers
6558 Codeforces 1452E: Two Editorials
6557 Codeforces 1452D: Radio Towers
6556 Codeforces 1452C: Two Brackets
6555 Codeforces 1452B: Toy Blocks
6554 Codeforces 1452A: Robot Program
6553 Codeforces 1451F: Nullify The Matrix
6552 Codeforces 1451E2: Bitwise Queries (Hard Version)
6551 Codeforces 1451E1: Bitwise Queries (Easy Version)
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