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)
2101	Codeforces 488B: Candy Boxes
2100	Codeforces 488A: Giga Tower
2099	Codeforces 487E: Tourists
2098	Codeforces 487D: Conveyor Belts
2097	Codeforces 487C: Prefix Product Sequence
2096	Codeforces 487B: Strip
2095	Codeforces 487A: Fight the Monster
2094	Codeforces 486E: LIS of Sequence
2093	Codeforces 486D: Valid Sets
2092	Codeforces 486C: Palindrome Transformation
2091	Codeforces 486B: OR in Matrix
2090	Codeforces 486A: Calculating Function
2089	Codeforces 485B: Valuable Resources
2088	Codeforces 485A: Factory
2087	Codeforces 484E: Sign on Fence
2086	Codeforces 484D: Kindergarten
2085	Codeforces 484C: Strange Sorting
2084	Codeforces 484B: Maximum Value
2083	Codeforces 484A: Bits
2082	Codeforces 483B: Friends and Presents
2081	Codeforces 483A: Counterexample
2080	Codeforces 482E: ELCA
2079	Codeforces 482D: Random Function and Tree
2078	Codeforces 482C: Game with Strings
2077	Codeforces 482B: Interesting Array
2076	Codeforces 482A: Diverse Permutation
2075	Codeforces 480E: Parking Lot
2074	Codeforces 480D: Parcels
2073	Codeforces 479E: Riding in a Lift
2072	Codeforces 479D: Long Jumps
2071	Codeforces 479C: Exams
2070	Codeforces 479B: Towers
2069	Codeforces 479A: Expression
2068	Codeforces 478E: Wavy numbers
2067	Codeforces 478D: Red-Green Towers
2066	Codeforces 478C: Table Decorations
2065	Codeforces 478B: Random Teams
2064	Codeforces 478A: Initial Bet
2063	Codeforces 477E: Dreamoon and Notepad
2062	Codeforces 477D: Dreamoon and Binary
2061	Codeforces 476E: Dreamoon and Strings
2060	Codeforces 476D: Dreamoon and Sets
2059	Codeforces 476C: Dreamoon and Sums
2058	Codeforces 476B: Dreamoon and WiFi
2057	Codeforces 476A: Dreamoon and Stairs
2056	Codeforces 475F: Meta-universe
2055	Codeforces 475E: Strongly Connected City 2
2054	Codeforces 475D: CGCDSSQ
2053	Codeforces 475C: Kamal-ol-molk's Painting
2052	Codeforces 475B: Strongly Connected City

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

2101

Codeforces 488B: Candy Boxes

2100

Codeforces 488A: Giga Tower

2099

Codeforces 487E: Tourists

2098

Codeforces 487D: Conveyor Belts

2097

Codeforces 487C: Prefix Product Sequence

2096