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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)
2650 Codeforces 624A: Save Luke
2649 Codeforces 623E: Transforming Sequence
2648 Codeforces 623D: Birthday
2647 Codeforces 623C: Electric Charges
2646 Codeforces 623B: Array GCD
2645 Codeforces 623A: Graph and String
2644 Codeforces 622F: The Sum of the k-th Powers
2643 Codeforces 622E: Ants in Leaves
2642 Codeforces 622D: Optimal Number Permutation
2641 Codeforces 622C: Not Equal on a Segment
2640 Codeforces 622B: The Time
2639 Codeforces 622A: Infinite Sequence
2638 Codeforces 621E: Wet Shark and Blocks
2637 Codeforces 621D: Rat Kwesh and Cheese
2636 Codeforces 621C: Wet Shark and Flowers
2635 Codeforces 621B: Wet Shark and Bishops
2634 Codeforces 621A: Wet Shark and Odd and Even
2633 Codeforces 620F: Xors on Segments
2632 Codeforces 620E: New Year Tree
2631 Codeforces 620D: Professor GukiZ and Two Arrays
2630 Codeforces 620C: Pearls in a Row
2629 Codeforces 620B: Grandfather Dovlet’s calculator
2628 Codeforces 620A: Professor GukiZ's Robot
2627 Codeforces 618G: Combining Slimes
2626 Codeforces 618F: Double Knapsack
2625 Codeforces 618E: Robot Arm
2624 Codeforces 618D: Hamiltonian Spanning Tree
2623 Codeforces 618C: Constellation
2622 Codeforces 618B: Guess the Permutation
2621 Codeforces 618A: Slime Combining
2620 Codeforces 617E: XOR and Favorite Number
2619 Codeforces 617D: Polyline
2618 Codeforces 617C: Watering Flowers
2617 Codeforces 617B: Chocolate
2616 Codeforces 617A: Elephant
2615 Codeforces 616F: Expensive Strings
2614 Codeforces 616E: Sum of Remainders
2613 Codeforces 616D: Longest k-Good Segment
2612 Codeforces 616C: The Labyrinth
2611 Codeforces 616B: Dinner with Emma
2610 Codeforces 616A: Comparing Two Long Integers
2609 Codeforces 615E: Hexagons
2608 Codeforces 615D: Multipliers
2607 Codeforces 615C: Running Track
2606 Codeforces 615B: Longtail Hedgehog
2605 Codeforces 615A: Bulbs
2604 Codeforces 614B: Gena's Code
2603 Codeforces 614A: Link/Cut Tree
2602 Codeforces 613E: Puzzle Lover
2601 Codeforces 613D: Kingdom and its Cities
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