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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)
4650 Codeforces 1080E: Sonya and Matrix Beauty
4649 Codeforces 1080D: Olya and magical square
4648 Codeforces 1080C: Masha and two friends
4647 Codeforces 1080B: Margarite and the best present
4646 Codeforces 1080A: Petya and Origami
4645 Codeforces 1078E: Negative Time Summation
4644 Codeforces 1077F2: Pictures with Kittens (hard version)
4643 Codeforces 1077F1: Pictures with Kittens (easy version)
4642 Codeforces 1077E: Thematic Contests
4641 Codeforces 1077D: Cutting Out
4640 Codeforces 1077C: Good Array
4639 Codeforces 1077B: Disturbed People
4638 Codeforces 1077A: Frog Jumping
4637 Codeforces 1076G: Array Game
4636 Codeforces 1076F: Summer Practice Report
4635 Codeforces 1076E: Vasya and a Tree
4634 Codeforces 1076D: Edge Deletion
4633 Codeforces 1076C: Meme Problem
4632 Codeforces 1076B: Divisor Subtraction
4631 Codeforces 1076A: Minimizing the String
4630 Codeforces 1075B: Taxi drivers and Lyft
4629 Codeforces 1075A: The King's Race
4628 Codeforces 1073G: Yet Another LCP Problem
4627 Codeforces 1073F: Choosing Two Paths
4626 Codeforces 1073E: Segment Sum
4625 Codeforces 1073D: Berland Fair
4624 Codeforces 1073C: Vasya and Robot
4623 Codeforces 1073B: Vasya and Books
4622 Codeforces 1073A: Diverse Substring
4621 Codeforces 1071E: Rain Protection
4620 Codeforces 1070M: Algoland and Berland
4619 Codeforces 1070L: Odd Federalization
4618 Codeforces 1070K: Video Posts
4617 Codeforces 1070J: Streets and Avenues in Berhattan
4616 Codeforces 1070I: Privatization of Roads in Berland
4615 Codeforces 1070H: BerOS File Suggestion
4614 Codeforces 1070G: Monsters and Potions
4613 Codeforces 1070F: Debate
4612 Codeforces 1070E: Getting Deals Done
4611 Codeforces 1070D: Garbage Disposal
4610 Codeforces 1070C: Cloud Computing
4609 Codeforces 1070B: Berkomnadzor
4608 Codeforces 1070A: Find a Number
4607 Codeforces 1068C: Colored Rooks
4606 Codeforces 1068B: LCM
4605 Codeforces 1068A: Birthday
4604 Codeforces 1067E: Random Forest Rank
4603 Codeforces 1067D: Computer Game
4602 Codeforces 1067C: Knights
4601 Codeforces 1067B: Multihedgehog
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