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)
7351	Codeforces 1606F: Tree Queries
7350	Codeforces 1606E: Arena
7349	Codeforces 1606D: Red-Blue Matrix
7348	Codeforces 1606C: Banknotes
7347	Codeforces 1606B: Update Files
7346	Codeforces 1606A: AB Balance
7345	Codeforces 1605F: PalindORme
7344	Codeforces 1605E: Array Equalizer
7343	Codeforces 1605D: Treelabeling
7342	Codeforces 1605C: Dominant Character
7341	Codeforces 1605B: Reverse Sort
7340	Codeforces 1605A: A.M. Deviation
7339	Codeforces 1604B: XOR Specia-LIS-t
7338	Codeforces 1604A: Era
7337	Codeforces 1603F: October 18, 2017
7336	Codeforces 1603E: A Perfect Problem
7335	Codeforces 1603D: Artistic Partition
7334	Codeforces 1603C: Extreme Extension
7333	Codeforces 1603B: Moderate Modular Mode
7332	Codeforces 1603A: Di-visible Confusion
7331	Codeforces 1602B: Divine Array
7330	Codeforces 1602A: Two Subsequences
7329	Codeforces 1601F: Two Sorts
7328	Codeforces 1601E: Phys Ed Online
7327	Codeforces 1601D: Difficult Mountain
7326	Codeforces 1601C: Optimal Insertion
7325	Codeforces 1601B: Frog Traveler
7324	Codeforces 1601A: Array Elimination
7323	Codeforces 1600J: Robot Factory
7322	Codeforces 1600F: Party Organization
7321	Codeforces 1600E: Array Game
7320	Codeforces 1599J: Bob's Beautiful Array
7319	Codeforces 1599I: Desert
7318	Codeforces 1599H: Hidden Fortress
7317	Codeforces 1599G: Shortest path
7316	Codeforces 1599F: Mars
7315	Codeforces 1599E: Two Arrays
7314	Codeforces 1599D: Bubble Popping
7313	Codeforces 1599C: Bubble Strike
7312	Codeforces 1599B: Restaurant Game
7311	Codeforces 1599A: Weights
7310	Codeforces 1598G: The Sum of Good Numbers
7309	Codeforces 1598F: RBS
7308	Codeforces 1598E: Staircases
7307	Codeforces 1598D: Training Session
7306	Codeforces 1598C: Delete Two Elements
7305	Codeforces 1598B: Groups
7304	Codeforces 1598A: Computer Game
7303	Codeforces 1594F: Ideal Farm
7302	Codeforces 1594E2: Rubik's Cube Coloring (hard version)

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

7351

Codeforces 1606F: Tree Queries

7350

Codeforces 1606E: Arena

7349

Codeforces 1606D: Red-Blue Matrix

7348

Codeforces 1606C: Banknotes

7347

Codeforces 1606B: Update Files

7346