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)
23451	USACO 2016 January Contest, Bronze: Mowing the Field
23450	USACO 2016 January Contest, Bronze: Angry Cows
23449	USACO 2016 January Contest, Bronze: Promotion Counting
23448	USACO 2016 January Contest, Silver: Build Gates
23447	USACO 2016 January Contest, Silver: Subsequences Summing to Sevens
23446	USACO 2016 January Contest, Silver: Angry Cows
23445	USACO 2016 January Contest, Gold: Lights Out
23444	USACO 2016 January Contest, Gold: Radio Contact
23443	USACO 2016 January Contest, Gold: Angry Cows
23442	USACO 2016 January Contest, Platinum: Lights Out
23441	USACO 2016 January Contest, Platinum: Mowing the Field
23440	USACO 2016 January Contest, Platinum: Fort Moo
23439	USACO 2016 December Contest, Bronze: The Cow-Signal
23438	USACO 2016 December Contest, Bronze: Block Game
23437	USACO 2016 December Contest, Bronze: Square Pasture
23436	USACO 2016 December Contest, Silver: Moocast
23435	USACO 2016 December Contest, Silver: Cities and States
23434	USACO 2016 December Contest, Silver: Counting Haybales
23433	USACO 2016 December Contest, Gold: Lasers and Mirrors
23432	USACO 2016 December Contest, Gold: Cow Checklist
23431	USACO 2016 December Contest, Gold: Moocast
23430	USACO 2016 December Contest, Platinum: Robotic Cow Herd
23429	USACO 2016 December Contest, Platinum: Team Building
23428	USACO 2016 December Contest, Platinum: Lots of Triangles
23427	USACO 2015 US Open, Bronze: Palindromic Paths (Bronze)
23426	USACO 2015 US Open, Bronze: Trapped in the Haybales (Bronze)
23425	USACO 2015 US Open, Bronze: Bessie Gets Even
23424	USACO 2015 US Open, Bronze: Moocryption
23423	USACO 2015 US Open, Silver: Bessie's Birthday Buffet
23422	USACO 2015 US Open, Silver: Trapped in the Haybales (Silver)
23421	USACO 2015 US Open, Silver: Bessie Goes Moo
23420	USACO 2015 US Open, Gold: Trapped in the Haybales (Gold)
23419	USACO 2015 US Open, Gold: Palindromic Paths
23418	USACO 2015 US Open, Gold: Googol
23417	USACO 2015 February Contest, Bronze: Cow Hopscotch (Bronze)
23416	USACO 2015 February Contest, Bronze: COW
23415	USACO 2015 February Contest, Bronze: Censoring (Bronze)
23414	USACO 2015 February Contest, Silver: Superbull
23413	USACO 2015 February Contest, Silver: Cow Hopscotch (Silver)
23412	USACO 2015 February Contest, Silver: Censoring (Silver)
23411	USACO 2015 February Contest, Gold: Fencing the Herd
23410	USACO 2015 February Contest, Gold: Censoring (Gold)
23409	USACO 2015 February Contest, Gold: Cow Hopscotch (Gold)
23408	USACO 2015 January Contest, Bronze: Meeting Time
23407	USACO 2015 January Contest, Bronze: It's All About the Base
23406	USACO 2015 January Contest, Bronze: Cow Routing II
23405	USACO 2015 January Contest, Bronze: Cow Routing
23404	USACO 2015 January Contest, Silver: Meeting Time
23403	USACO 2015 January Contest, Silver: Cow Routing
23402	USACO 2015 January Contest, Silver: Stampede

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

23451

USACO 2016 January Contest, Bronze: Mowing the Field

23450

USACO 2016 January Contest, Bronze: Angry Cows

23449

USACO 2016 January Contest, Bronze: Promotion Counting

23448

USACO 2016 January Contest, Silver: Build Gates

23447

USACO 2016 January Contest, Silver: Subsequences Summing to Sevens

23446