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)
8251	Codeforces 1764D: Doremy's Pegging Game
8250	Codeforces 1764C: Doremy's City Construction
8249	Codeforces 1764B: Doremy's Perfect Math Class
8248	Codeforces 1764A: Doremy's Paint
8247	Codeforces 1763F: Edge Queries
8246	Codeforces 1763E: Node Pairs
8245	Codeforces 1763D: Valid Bitonic Permutations
8244	Codeforces 1763C: Another Array Problem
8243	Codeforces 1763B: Incinerate
8242	Codeforces 1763A: Absolute Maximization
8241	Codeforces 1762G: Unequal Adjacent Elements
8240	Codeforces 1762F: Good Pairs
8239	Codeforces 1762E: Tree Sum
8238	Codeforces 1762D: GCD Queries
8237	Codeforces 1762C: Binary Strings are Fun
8236	Codeforces 1762B: Make Array Good
8235	Codeforces 1762A: Divide and Conquer
8234	Codeforces 1761G: Centroid Guess
8233	Codeforces 1761F2: Anti-median (Hard Version)
8232	Codeforces 1761F1: Anti-median (Easy Version)
8231	Codeforces 1761E: Make It Connected
8230	Codeforces 1761D: Carry Bit
8229	Codeforces 1761C: Set Construction
8228	Codeforces 1761B: Elimination of a Ring
8227	Codeforces 1761A: Two Permutations
8226	Codeforces 1760G: SlavicG's Favorite Problem
8225	Codeforces 1760F: Quests
8224	Codeforces 1760E: Binary Inversions
8223	Codeforces 1760D: Challenging Valleys
8222	Codeforces 1760C: Advantage
8221	Codeforces 1760B: Atilla's Favorite Problem
8220	Codeforces 1760A: Medium Number
8219	Codeforces 1759G: Restore the Permutation
8218	Codeforces 1759F: All Possible Digits
8217	Codeforces 1759E: The Humanoid
8216	Codeforces 1759D: Make It Round
8215	Codeforces 1759C: Thermostat
8214	Codeforces 1759B: Lost Permutation
8213	Codeforces 1759A: Yes-Yes?
8212	Codeforces 1758F: Decent Division
8211	Codeforces 1758E: Tick, Tock
8210	Codeforces 1758D: Range = √Sum
8209	Codeforces 1758C: Almost All Multiples
8208	Codeforces 1758B: XOR = Average
8207	Codeforces 1758A: SSeeeeiinngg DDoouubbllee
8206	Codeforces 1754B: Kevin and Permutation
8205	Codeforces 1754A: Technical Support
8204	Codeforces 1753F: Minecraft Series
8203	Codeforces 1753E: N Machines
8202	Codeforces 1753D: The Beach

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

8251

Codeforces 1764D: Doremy's Pegging Game

8250

Codeforces 1764C: Doremy's City Construction

8249

Codeforces 1764B: Doremy's Perfect Math Class

8248

Codeforces 1764A: Doremy's Paint

8247

Codeforces 1763F: Edge Queries

8246