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)
2151	Codeforces 500D: New Year Santa Network
2150	Codeforces 500C: New Year Book Reading
2149	Codeforces 500B: New Year Permutation
2148	Codeforces 500A: New Year Transportation
2147	Codeforces 499B: Lecture
2146	Codeforces 499A: Watching a movie
2145	Codeforces 498E: Stairs and Lines
2144	Codeforces 498D: Traffic Jams in the Land
2143	Codeforces 498C: Array and Operations
2142	Codeforces 498B: Name That Tune
2141	Codeforces 498A: Crazy Town
2140	Codeforces 497E: Subsequences Return
2139	Codeforces 497D: Gears
2138	Codeforces 496E: Distributing Parts
2137	Codeforces 496D: Tennis Game
2136	Codeforces 496C: Removing Columns
2135	Codeforces 496B: Secret Combination
2134	Codeforces 496A: Minimum Difficulty
2133	Codeforces 495B: Modular Equations
2132	Codeforces 495A: Digital Counter
2131	Codeforces 494E: Sharti
2130	Codeforces 494D: Birthday
2129	Codeforces 494C: Helping People
2128	Codeforces 494B: Obsessive String
2127	Codeforces 494A: Treasure
2126	Codeforces 493E: Vasya and Polynomial
2125	Codeforces 493D: Vasya and Chess
2124	Codeforces 493C: Vasya and Basketball
2123	Codeforces 493B: Vasya and Wrestling
2122	Codeforces 493A: Vasya and Football
2121	Codeforces 492E: Vanya and Field
2120	Codeforces 492D: Vanya and Computer Game
2119	Codeforces 492C: Vanya and Exams
2118	Codeforces 492B: Vanya and Lanterns
2117	Codeforces 492A: Vanya and Cubes
2116	Codeforces 491C: Deciphering
2115	Codeforces 491B: New York Hotel
2114	Codeforces 491A: Up the hill
2113	Codeforces 490F: Treeland Tour
2112	Codeforces 490E: Restoring Increasing Sequence
2111	Codeforces 490D: Chocolate
2110	Codeforces 490C: Hacking Cypher
2109	Codeforces 490B: Queue
2108	Codeforces 490A: Team Olympiad
2107	Codeforces 489F: Special Matrices
2106	Codeforces 489E: Hiking
2105	Codeforces 489D: Unbearable Controversy of Being
2104	Codeforces 489C: Given Length and Sum of Digits...
2103	Codeforces 489B: BerSU Ball
2102	Codeforces 489A: SwapSort

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

2151

Codeforces 500D: New Year Santa Network

2150

Codeforces 500C: New Year Book Reading

2149

Codeforces 500B: New Year Permutation

2148

Codeforces 500A: New Year Transportation

2147

Codeforces 499B: Lecture

2146