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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)
7600 Codeforces 1650A: Deletions of Two Adjacent Letters
7599 Codeforces 1649B: Game of Ball Passing
7598 Codeforces 1649A: Game
7597 Codeforces 1648F: Two Avenues
7596 Codeforces 1648E: Air Reform
7595 Codeforces 1648D: Serious Business
7594 Codeforces 1648C: Tyler and Strings
7593 Codeforces 1648B: Integral Array
7592 Codeforces 1648A: Weird Sum
7591 Codeforces 1647F: Madoka and Laziness
7590 Codeforces 1647E: Madoka and the Sixth-graders
7589 Codeforces 1647D: Madoka and the Best School in Russia
7588 Codeforces 1647C: Madoka and Childish Pranks
7587 Codeforces 1647B: Madoka and the Elegant Gift
7586 Codeforces 1647A: Madoka and Math Dad
7585 Codeforces 1646F: Playing Around the Table
7584 Codeforces 1646E: Power Board
7583 Codeforces 1646D: Weight the Tree
7582 Codeforces 1646C: Factorials and Powers of Two
7581 Codeforces 1646B: Quality vs Quantity
7580 Codeforces 1646A: Square Counting
7579 Codeforces 1644F: Basis
7578 Codeforces 1644E: Expand the Path
7577 Codeforces 1644D: Cross Coloring
7576 Codeforces 1644C: Increase Subarray Sums
7575 Codeforces 1644B: Anti-Fibonacci Permutation
7574 Codeforces 1644A: Doors and Keys
7573 Codeforces 1642B: Power Walking
7572 Codeforces 1642A: Hard Way
7571 Codeforces 1641F: Covering Circle
7570 Codeforces 1641E: Special Positions
7569 Codeforces 1641D: Two Arrays
7568 Codeforces 1641C: Anonymity Is Important
7567 Codeforces 1641B: Repetitions Decoding
7566 Codeforces 1641A: Great Sequence
7565 Codeforces 1639K: Treasure Hunt
7564 Codeforces 1639J: Treasure Hunt
7563 Codeforces 1639I: Treasure Hunt
7562 Codeforces 1639H: Treasure Hunt
7561 Codeforces 1639G: Treasure Hunt
7560 Codeforces 1639F: Treasure Hunt
7559 Codeforces 1639E: Treasure Hunt
7558 Codeforces 1639D: Treasure Hunt
7557 Codeforces 1639C: Treasure Hunt
7556 Codeforces 1639B: Treasure Hunt
7555 Codeforces 1639A: Treasure Hunt
7554 Codeforces 1638F: Two Posters
7553 Codeforces 1638E: Colorful Operations
7552 Codeforces 1638D: Big Brush
7551 Codeforces 1638C: Inversion Graph
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