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.

Need help searching? Click for format/examples of problems

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)
23701	USACO 2021 February Contest, Bronze: Comfortable Cows
23700	USACO 2021 February Contest, Bronze: Year of the Cow
23699	USACO 2021 February Contest, Silver: Just Green Enough
23698	USACO 2021 February Contest, Silver: Year of the Cow
23697	USACO 2021 February Contest, Silver: Comfortable Cows
23696	USACO 2021 February Contest, Gold: Count the Cows
23695	USACO 2021 February Contest, Gold: Modern Art 3
23694	USACO 2021 February Contest, Gold: Stone Game
23693	USACO 2021 February Contest, Platinum: Counting Graphs
23692	USACO 2021 February Contest, Platinum: Minimizing Edges
23691	USACO 2021 February Contest, Platinum: No Time to Dry
23690	USACO 2021 January Contest, Bronze: Just Stalling
23689	USACO 2021 January Contest, Bronze: Even More Odd Photos
23688	USACO 2021 January Contest, Bronze: Uddered but not Herd
23687	USACO 2021 January Contest, Silver: Spaced Out
23686	USACO 2021 January Contest, Silver: No Time to Paint
23685	USACO 2021 January Contest, Silver: Dance Mooves
23684	USACO 2021 January Contest, Gold: Dance Mooves
23683	USACO 2021 January Contest, Gold: Telephone
23682	USACO 2021 January Contest, Gold: Uddered but not Herd
23681	USACO 2021 January Contest, Platinum: Paint by Letters
23680	USACO 2021 January Contest, Platinum: Minimum Cost Paths
23679	USACO 2021 January Contest, Platinum: Sum of Distances
23678	USACO 2021 December Contest, Bronze: Walking Home
23677	USACO 2021 December Contest, Bronze: Air Cownditioning
23676	USACO 2021 December Contest, Bronze: Lonely Photo
23675	USACO 2021 December Contest, Silver: Convoluted Intervals
23674	USACO 2021 December Contest, Silver: Connecting Two Barns
23673	USACO 2021 December Contest, Silver: Closest Cow Wins
23672	USACO 2021 December Contest, Gold: Bracelet Crossings
23671	USACO 2021 December Contest, Gold: HILO
23670	USACO 2021 December Contest, Gold: Paired Up
23669	USACO 2021 December Contest, Platinum: HILO
23668	USACO 2021 December Contest, Platinum: Paired Up
23667	USACO 2021 December Contest, Platinum: Tickets
23666	USACO 2020 US Open Contest, Bronze: Cowntact Tracing
23665	USACO 2020 US Open Contest, Bronze: Social Distancing II
23664	USACO 2020 US Open Contest, Bronze: Social Distancing I
23663	USACO 2020 US Open Contest, Silver: The Moo Particle
23662	USACO 2020 US Open Contest, Silver: Cereal
23661	USACO 2020 US Open Contest, Silver: Social Distancing
23660	USACO 2020 US Open Contest, Gold: Exercise
23659	USACO 2020 US Open Contest, Gold: Favorite Colors
23658	USACO 2020 US Open Contest, Gold: Haircut
23657	USACO 2020 US Open Contest, Platinum: Circus
23656	USACO 2020 US Open Contest, Platinum: Exercise
23655	USACO 2020 US Open Contest, Platinum: Sprinklers 2: Return of the Alfalfa
23654	USACO 2020 February Contest, Bronze: Swapity Swap
23653	USACO 2020 February Contest, Bronze: Mad Scientist
23652	USACO 2020 February Contest, Bronze: Triangles

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

23701

USACO 2021 February Contest, Bronze: Comfortable Cows

23700

USACO 2021 February Contest, Bronze: Year of the Cow

23699

USACO 2021 February Contest, Silver: Just Green Enough

23698

USACO 2021 February Contest, Silver: Year of the Cow

23697

USACO 2021 February Contest, Silver: Comfortable Cows

23696