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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)
8700 Codeforces 1835D: Doctor's Brown Hypothesis
8699 Codeforces 1835C: Twin Clusters
8698 Codeforces 1835B: Lottery
8697 Codeforces 1835A: k-th equality
8696 Codeforces 1834F: Typewriter
8695 Codeforces 1834E: MEX of LCM
8694 Codeforces 1834D: Survey in Class
8693 Codeforces 1834C: Game with Reversing
8692 Codeforces 1834B: Maximum Strength
8691 Codeforces 1834A: Unit Array
8690 Codeforces 1833G: Ksyusha and Chinchilla
8689 Codeforces 1833F: Ira and Flamenco
8688 Codeforces 1833E: Round Dance
8687 Codeforces 1833D: Flipper
8686 Codeforces 1833C: Vlad Building Beautiful Array
8685 Codeforces 1833B: Restore the Weather
8684 Codeforces 1833A: Musical Puzzle
8683 Codeforces 1832F: Zombies
8682 Codeforces 1832E: Combinatorics Problem
8681 Codeforces 1832D2: Red-Blue Operations (Hard Version)
8680 Codeforces 1832D1: Red-Blue Operations (Easy Version)
8679 Codeforces 1832C: Contrast Value
8678 Codeforces 1832B: Maximum Sum
8677 Codeforces 1832A: New Palindrome
8676 Codeforces 1831B: Array merging
8675 Codeforces 1831A: Twin Permutations
8674 Codeforces 1830F: The Third Grace
8673 Codeforces 1830E: Bully Sort
8672 Codeforces 1830D: Mex Tree
8671 Codeforces 1830C: Hyperregular Bracket Strings
8670 Codeforces 1830B: The BOSS Can Count Pairs
8669 Codeforces 1830A: Copil Copac Draws Trees
8668 Codeforces 1829H: Don't Blame Me
8667 Codeforces 1829G: Hits Different
8666 Codeforces 1829F: Forever Winter
8665 Codeforces 1829E: The Lakes
8664 Codeforces 1829D: Gold Rush
8663 Codeforces 1829C: Mr. Perfectly Fine
8662 Codeforces 1829B: Blank Space
8661 Codeforces 1829A: Love Story
8660 Codeforces 1828B: Permutation Swap
8659 Codeforces 1828A: Divisible Array
8658 Codeforces 1827F: Copium Permutation
8657 Codeforces 1827E: Bus Routes
8656 Codeforces 1827D: Two Centroids
8655 Codeforces 1827C: Palindrome Partition
8654 Codeforces 1827B2: Range Sorting (Hard Version)
8653 Codeforces 1827B1: Range Sorting (Easy Version)
8652 Codeforces 1827A: Counting Orders
8651 Codeforces 1826F: Fading into Fog
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