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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)
6800 Codeforces 1499A: Domino on Windowsill
6799 Codeforces 1498F: Christmas Game
6798 Codeforces 1498E: Two Houses
6797 Codeforces 1498D: Bananas in a Microwave
6796 Codeforces 1498C: Planar Reflections
6795 Codeforces 1498B: Box Fitting
6794 Codeforces 1498A: GCD Sum
6793 Codeforces 1497E2: Square-free division (hard version)
6792 Codeforces 1497E1: Square-Free Division (easy version)
6791 Codeforces 1497D: Genius
6790 Codeforces 1497C2: k-LCM (hard version)
6789 Codeforces 1497C1: k-LCM (easy version)
6788 Codeforces 1497B: M-arrays
6787 Codeforces 1497A: Meximization
6786 Codeforces 1496B: Max and Mex
6785 Codeforces 1496A: Split it!
6784 Codeforces 1495F: Squares
6783 Codeforces 1495E: Qingshan and Daniel
6782 Codeforces 1495D: BFS Trees
6781 Codeforces 1495C: Garden of the Sun
6780 Codeforces 1495B: Let's Go Hiking
6779 Codeforces 1495A: Diamond Miner
6778 Codeforces 1494F: Delete The Edges
6777 Codeforces 1494E: A-Z Graph
6776 Codeforces 1494D: Dogeforces
6775 Codeforces 1494C: 1D Sokoban
6774 Codeforces 1494B: Berland Crossword
6773 Codeforces 1494A: ABC String
6772 Codeforces 1493F: Enchanted Matrix
6771 Codeforces 1493E: Enormous XOR
6770 Codeforces 1493D: GCD of an Array
6769 Codeforces 1493C: K-beautiful Strings
6768 Codeforces 1493B: Planet Lapituletti
6767 Codeforces 1493A: Anti-knapsack
6766 Codeforces 1492E: Almost Fault-Tolerant Database
6765 Codeforces 1492D: Genius's Gambit
6764 Codeforces 1492C: Maximum width
6763 Codeforces 1492B: Card Deck
6762 Codeforces 1492A: Three swimmers
6761 Codeforces 1491I: Ruler Of The Zoo
6760 Codeforces 1491H: Yuezheng Ling and Dynamic Tree
6759 Codeforces 1491G: Switch and Flip
6758 Codeforces 1491F: Magnets
6757 Codeforces 1491E: Fib-tree
6756 Codeforces 1491D: Zookeeper and The Infinite Zoo
6755 Codeforces 1491C: Pekora and Trampoline
6754 Codeforces 1491B: Minimal Cost
6753 Codeforces 1491A: K-th Largest Value
6752 Codeforces 1490G: Old Floppy Drive
6751 Codeforces 1490F: Equalize the Array
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