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)
3951	Codeforces 922F: Divisibility
3950	Codeforces 922E: Birds
3949	Codeforces 922D: Robot Vacuum Cleaner
3948	Codeforces 922C: Cave Painting
3947	Codeforces 922B: Magic Forest
3946	Codeforces 922A: Cloning Toys
3945	Codeforces 92114: Labyrinth-14
3944	Codeforces 92113: Labyrinth-13
3943	Codeforces 92112: Labyrinth-12
3942	Codeforces 92111: Labyrinth-11
3941	Codeforces 92110: Labyrinth-10
3940	Codeforces 92109: Labyrinth-9
3939	Codeforces 92108: Labyrinth-8
3938	Codeforces 92107: Labyrinth-7
3937	Codeforces 92106: Labyrinth-6
3936	Codeforces 92105: Labyrinth-5
3935	Codeforces 92104: Labyrinth-4
3934	Codeforces 92103: Labyrinth-3
3933	Codeforces 92102: Labyrinth-2
3932	Codeforces 92101: Labyrinth-1
3931	Codeforces 920G: List Of Integers
3930	Codeforces 920F: SUM and REPLACE
3929	Codeforces 920E: Connected Components?
3928	Codeforces 920D: Tanks
3927	Codeforces 920C: Swap Adjacent Elements
3926	Codeforces 920B: Tea Queue
3925	Codeforces 920A: Water The Garden
3924	Codeforces 919F: A Game With Numbers
3923	Codeforces 919E: Congruence Equation
3922	Codeforces 919D: Substring
3921	Codeforces 919C: Seat Arrangements
3920	Codeforces 919B: Perfect Number
3919	Codeforces 919A: Supermarket
3918	Codeforces 918B: Radio Station
3917	Codeforces 918A: Eleven
3916	Codeforces 917E: Upside Down
3915	Codeforces 917D: Stranger Trees
3914	Codeforces 917C: Pollywog
3913	Codeforces 917B: MADMAX
3912	Codeforces 917A: The Monster
3911	Codeforces 916E: Jamie and Tree
3910	Codeforces 916D: Jamie and To-do List
3909	Codeforces 916C: Jamie and Interesting Graph
3908	Codeforces 916B: Jamie and Binary Sequence (changed after round)
3907	Codeforces 916A: Jamie and Alarm Snooze
3906	Codeforces 915G: Coprime Arrays
3905	Codeforces 915F: Imbalance Value of a Tree
3904	Codeforces 915E: Physical Education Lessons
3903	Codeforces 915D: Almost Acyclic Graph
3902	Codeforces 915C: Permute Digits

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

3951

Codeforces 922F: Divisibility

3950

Codeforces 922E: Birds

3949

Codeforces 922D: Robot Vacuum Cleaner

3948

Codeforces 922C: Cave Painting

3947

Codeforces 922B: Magic Forest

3946