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)
5001	Codeforces 1148D: Dirty Deeds Done Dirt Cheap
5000	Codeforces 1148C: Crazy Diamond
4999	Codeforces 1148B: Born This Way
4998	Codeforces 1148A: Another One Bites The Dust
4997	Codeforces 1147F: Zigzag Game
4996	Codeforces 1147E: Rainbow Coins
4995	Codeforces 1147D: Palindrome XOR
4994	Codeforces 1147C: Thanos Nim
4993	Codeforces 1147B: Chladni Figure
4992	Codeforces 1147A: Hide and Seek
4991	Codeforces 1146H: Satanic Panic
4990	Codeforces 1146G: Zoning Restrictions
4989	Codeforces 1146F: Leaf Partition
4988	Codeforces 1146E: Hot is Cold
4987	Codeforces 1146D: Frog Jumping
4986	Codeforces 1146C: Tree Diameter
4985	Codeforces 1146B: Hate "A"
4984	Codeforces 1146A: Love "A"
4983	Codeforces 1145G: AI Takeover
4982	Codeforces 1145F: Neat Words
4981	Codeforces 1145E: Fourier Doodles
4980	Codeforces 1145D: Pigeon d'Or
4979	Codeforces 1145C: Mystery Circuit
4978	Codeforces 1145B: Kanban Numbers
4977	Codeforces 1145A: Thanos Sort
4976	Codeforces 1144G: Two Merged Sequences
4975	Codeforces 1144F: Graph Without Long Directed Paths
4974	Codeforces 1144E: Median String
4973	Codeforces 1144D: Equalize Them All
4972	Codeforces 1144C: Two Shuffled Sequences
4971	Codeforces 1144B: Parity Alternated Deletions
4970	Codeforces 1144A: Diverse Strings
4969	Codeforces 1143C: Queen
4968	Codeforces 1143B: Nirvana
4967	Codeforces 1143A: The Doors
4966	Codeforces 1142E: Pink Floyd
4965	Codeforces 1142D: Foreigner
4964	Codeforces 1142C: U2
4963	Codeforces 1142B: Lynyrd Skynyrd
4962	Codeforces 1142A: The Beatles
4961	Codeforces 1141G: Privatization of Roads in Treeland
4960	Codeforces 1141F2: Same Sum Blocks (Hard)
4959	Codeforces 1141F1: Same Sum Blocks (Easy)
4958	Codeforces 1141E: Superhero Battle
4957	Codeforces 1141D: Colored Boots
4956	Codeforces 1141C: Polycarp Restores Permutation
4955	Codeforces 1141B: Maximal Continuous Rest
4954	Codeforces 1141A: Game 23
4953	Codeforces 1140G: Double Tree
4952	Codeforces 1140F: Extending Set of Points

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

5001

Codeforces 1148D: Dirty Deeds Done Dirt Cheap

5000

Codeforces 1148C: Crazy Diamond

4999

Codeforces 1148B: Born This Way

4998

Codeforces 1148A: Another One Bites The Dust

4997

Codeforces 1147F: Zigzag Game

4996