Starlight: List of Problems

Over 20,000 problems available. AMC 8/10/12 and AIME problems from 2010-2023; USAJMO/USAMO problems from 2002-2023 available. USACO problems from 2014 to 2023 (all divisions). Codeforces, AtCoder, DMOJ problems are added daily around 04:00 AM UTC, which may cause disruptions.

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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)
2851	Codeforces 676C: Vasya and String
2850	Codeforces 676B: Pyramid of Glasses
2849	Codeforces 676A: Nicholas and Permutation
2848	Codeforces 675E: Trains and Statistic
2847	Codeforces 675D: Tree Construction
2846	Codeforces 675C: Money Transfers
2845	Codeforces 675B: Restoring Painting
2844	Codeforces 675A: Infinite Sequence
2843	Codeforces 673B: Problems for Round
2842	Codeforces 673A: Bear and Game
2841	Codeforces 672B: Different is Good
2840	Codeforces 672A: Summer Camp
2839	Codeforces 671E: Organizing a Race
2838	Codeforces 671D: Roads in Yusland
2837	Codeforces 671C: Ultimate Weirdness of an Array
2836	Codeforces 671B: Robin Hood
2835	Codeforces 671A: Recycling Bottles
2834	Codeforces 670F: Restore a Number
2833	Codeforces 670E: Correct Bracket Sequence Editor
2832	Codeforces 670D2: Magic Powder - 2
2831	Codeforces 670D1: Magic Powder - 1
2830	Codeforces 670C: Cinema
2829	Codeforces 670B: Game of Robots
2828	Codeforces 670A: Holidays
2827	Codeforces 669A: Little Artem and Presents
2826	Codeforces 667B: Coat of Anticubism
2825	Codeforces 667A: Pouring Rain
2824	Codeforces 666E: Forensic Examination
2823	Codeforces 666D: Chain Reaction
2822	Codeforces 666C: Codeword
2821	Codeforces 666B: World Tour
2820	Codeforces 666A: Reberland Linguistics
2819	Codeforces 665F: Four Divisors
2818	Codeforces 665E: Beautiful Subarrays
2817	Codeforces 665D: Simple Subset
2816	Codeforces 665C: Simple Strings
2815	Codeforces 665B: Shopping
2814	Codeforces 665A: Buses Between Cities
2813	Codeforces 664A: Complicated GCD
2812	Codeforces 663A: Rebus
2811	Codeforces 662E: To Hack or not to Hack
2810	Codeforces 662D: International Olympiad
2809	Codeforces 662C: Binary Table
2808	Codeforces 662B: Graph Coloring
2807	Codeforces 662A: Gambling Nim
2806	Codeforces 661H: Rotate Matrix
2805	Codeforces 661G: Hungarian Notation
2804	Codeforces 661F: Primes in Interval
2803	Codeforces 661E: Divisibility Check
2802	Codeforces 661D: Maximal Difference

Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)

2851

Codeforces 676C: Vasya and String

2850

Codeforces 676B: Pyramid of Glasses

2849

Codeforces 676A: Nicholas and Permutation

2848

Codeforces 675E: Trains and Statistic

2847

Codeforces 675D: Tree Construction

2846