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)
17151	DMOJ DMOPC '22 Contest 1 P3 - Group Project
17150	DMOJ DMOPC '22 Contest 1 P2 - Hat Swap
17149	DMOJ DMOPC '22 Contest 1 P1 - Up-down Sequence
17148	DMOJ DMOPC '21 Contest 9 P6 - Shortest Paths
17147	DMOJ DMOPC '21 Contest 9 P5 - Chika Circle
17146	DMOJ DMOPC '21 Contest 9 P4 - Ace of Diamonds
17145	DMOJ DMOPC '21 Contest 9 P3 - Terrible Trains
17144	DMOJ DMOPC '21 Contest 9 P2 - String Puzzle
17143	DMOJ DMOPC '21 Contest 9 P1 - Board Numbers
17142	DMOJ DMOPC '21 Contest 8 P6 - Castle Building
17141	DMOJ DMOPC '21 Contest 8 P5 - Tree Building
17140	DMOJ DMOPC '21 Contest 8 P4 - Grid Operations
17139	DMOJ DMOPC '21 Contest 8 P3 - Weaker Data
17138	DMOJ DMOPC '21 Contest 8 P2 - Kanna Market
17137	DMOJ DMOPC '21 Contest 8 P1 - Peanut Planning
17136	DMOJ DMOPC '21 Contest 7 P6 - Rainbow Subgraphs
17135	DMOJ DMOPC '21 Contest 7 P5 - King's Commands
17134	DMOJ DMOPC '21 Contest 7 P4 - Rocket Race
17133	DMOJ DMOPC '21 Contest 7 P3 - Whack-an-Ishigami
17132	DMOJ DMOPC '21 Contest 7 P2 - Knitting Scarves
17131	DMOJ DMOPC '21 Contest 7 P1 - Chika Grids
17130	DMOJ DMOPC '21 Contest 6 P5 - Contraband Game
17129	DMOJ DMOPC '21 Contest 6 P4 - Colourful Paths
17128	DMOJ DMOPC '21 Contest 6 P3 - An Art Problem
17127	DMOJ DMOPC '21 Contest 6 P2 - Gacha Luck
17126	DMOJ DMOPC '21 Contest 6 P1 - Bigger Big Integer
17125	DMOJ DMOPC '21 Contest 5 P6 - Permutations & Primes
17124	DMOJ DMOPC '21 Contest 5 P5 - Permutations & Primes (Hard Version)
17123	DMOJ DMOPC '21 Contest 5 P5 - Permutations & Primes
17122	DMOJ DMOPC '21 Contest 5 P4 - Permutations & Primes
17121	DMOJ DMOPC '21 Contest 5 P3 - Permutations & Primes
17120	DMOJ DMOPC '21 Contest 5 P2 - Permutations & Primes
17119	DMOJ DMOPC '21 Contest 5 P1 - Permutations & Primes
17118	DMOJ DMOPC '21 Contest 4 P6 - Balanced Line
17117	DMOJ DMOPC '21 Contest 4 P5 - Graph Generator
17116	DMOJ DMOPC '21 Contest 4 P4 - Christmas Graph
17115	DMOJ DMOPC '21 Contest 4 P3 - Palindromic Presents
17114	DMOJ DMOPC '21 Contest 4 P2 - Festive Groups
17113	DMOJ DMOPC '21 Contest 4 P1 - Tree Shopping
17112	DMOJ DMOPC '21 Contest 3 P6 - Good Grids
17111	DMOJ DMOPC '21 Contest 3 P5 - Crowded Travels
17110	DMOJ DMOPC '21 Contest 3 P4 - Sorting Subsequences
17109	DMOJ DMOPC '21 Contest 3 P3 - Hopping Frogs
17108	DMOJ DMOPC '21 Contest 3 P2 - Weak Data
17107	DMOJ DMOPC '21 Contest 3 P1 - Sums & Differences
17106	DMOJ DMOPC '21 Contest 2 P6 - Strange Function
17105	DMOJ DMOPC '21 Contest 2 P5 - Permutations
17104	DMOJ DMOPC '21 Contest 2 P4 - Water Mechanics
17103	DMOJ DMOPC '21 Contest 2 P3 - Divisions
17102	DMOJ DMOPC '21 Contest 2 P2 - Scrambling Swaps

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

17151

DMOJ DMOPC '22 Contest 1 P3 - Group Project

17150

DMOJ DMOPC '22 Contest 1 P2 - Hat Swap

17149

DMOJ DMOPC '22 Contest 1 P1 - Up-down Sequence

17148

DMOJ DMOPC '21 Contest 9 P6 - Shortest Paths

17147

DMOJ DMOPC '21 Contest 9 P5 - Chika Circle

17146