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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)
2750 Codeforces 644C: Hostname Aliases
2749 Codeforces 644B: Processing Queries
2748 Codeforces 644A: Parliament of Berland
2747 Codeforces 643G: Choosing Ads
2746 Codeforces 643F: Bears and Juice
2745 Codeforces 643E: Bear and Destroying Subtrees
2744 Codeforces 643D: Bearish Fanpages
2743 Codeforces 643C: Levels and Regions
2742 Codeforces 643B: Bear and Two Paths
2741 Codeforces 643A: Bear and Colors
2740 Codeforces 641G: Little Artem and Graph
2739 Codeforces 641F: Little Artem and 2-SAT
2738 Codeforces 641E: Little Artem and Time Machine
2737 Codeforces 641D: Little Artem and Random Variable
2736 Codeforces 641C: Little Artem and Dance
2735 Codeforces 641B: Little Artem and Matrix
2734 Codeforces 641A: Little Artem and Grasshopper
2733 Codeforces 639F: Bear and Chemistry
2732 Codeforces 639E: Bear and Paradox
2731 Codeforces 639D: Bear and Contribution
2730 Codeforces 639C: Bear and Polynomials
2729 Codeforces 639B: Bear and Forgotten Tree 3
2728 Codeforces 639A: Bear and Displayed Friends
2727 Codeforces 638D: Three-dimensional Turtle Super Computer
2726 Codeforces 638C: Road Improvement
2725 Codeforces 638B: Making Genome in Berland
2724 Codeforces 638A: Home Numbers
2723 Codeforces 637D: Running with Obstacles
2722 Codeforces 637C: Promocodes with Mistakes
2721 Codeforces 637B: Chat Order
2720 Codeforces 637A: Voting for Photos
2719 Codeforces 635A: Orchestra
2718 Codeforces 634A: Island Puzzle
2717 Codeforces 633H: Fibonacci-ish II
2716 Codeforces 633G: Yash And Trees
2715 Codeforces 633F: The Chocolate Spree
2714 Codeforces 633E: Startup Funding
2713 Codeforces 633D: Fibonacci-ish
2712 Codeforces 633C: Spy Syndrome 2
2711 Codeforces 633B: A Trivial Problem
2710 Codeforces 633A: Ebony and Ivory
2709 Codeforces 632F: Magic Matrix
2708 Codeforces 632E: Thief in a Shop
2707 Codeforces 632D: Longest Subsequence
2706 Codeforces 632C: The Smallest String Concatenation
2705 Codeforces 632B: Alice, Bob, Two Teams
2704 Codeforces 632A: Grandma Laura and Apples
2703 Codeforces 631E: Product Sum
2702 Codeforces 631D: Messenger
2701 Codeforces 631C: Report
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