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)
6201	Codeforces 1379E: Inverse Genealogy
6200	Codeforces 1379D: New Passenger Trams
6199	Codeforces 1379C: Choosing flowers
6198	Codeforces 1379B: Dubious Cyrpto
6197	Codeforces 1379A: Acacius and String
6196	Codeforces 1375I: Cubic Lattice
6195	Codeforces 1375H: Set Merging
6194	Codeforces 1375G: Tree Modification
6193	Codeforces 1375F: Integer Game
6192	Codeforces 1375E: Inversion SwapSort
6191	Codeforces 1375D: Replace by MEX
6190	Codeforces 1375C: Element Extermination
6189	Codeforces 1375B: Neighbor Grid
6188	Codeforces 1375A: Sign Flipping
6187	Codeforces 1374F: Cyclic Shifts Sorting
6186	Codeforces 1374E2: Reading Books (hard version)
6185	Codeforces 1374E1: Reading Books (easy version)
6184	Codeforces 1374D: Zero Remainder Array
6183	Codeforces 1374C: Move Brackets
6182	Codeforces 1374B: Multiply by 2, divide by 6
6181	Codeforces 1374A: Required Remainder
6180	Codeforces 1373G: Pawns
6179	Codeforces 1373F: Network Coverage
6178	Codeforces 1373E: Sum of Digits
6177	Codeforces 1373D: Maximum Sum on Even Positions
6176	Codeforces 1373C: Pluses and Minuses
6175	Codeforces 1373B: 01 Game
6174	Codeforces 1373A: Donut Shops
6173	Codeforces 1372F: Omkar and Modes
6172	Codeforces 1372E: Omkar and Last Floor
6171	Codeforces 1372D: Omkar and Circle
6170	Codeforces 1372C: Omkar and Baseball
6169	Codeforces 1372B: Omkar and Last Class of Math
6168	Codeforces 1372A: Omkar and Completion
6167	Codeforces 1371F: Raging Thunder
6166	Codeforces 1371E2: Asterism (Hard Version)
6165	Codeforces 1371E1: Asterism (Easy Version)
6164	Codeforces 1371D: Grid-00100
6163	Codeforces 1371C: A Cookie for You
6162	Codeforces 1371B: Magical Calendar
6161	Codeforces 1371A: Magical Sticks
6160	Codeforces 1370F2: The Hidden Pair (Hard Version)
6159	Codeforces 1370F1: The Hidden Pair (Easy Version)
6158	Codeforces 1370E: Binary Subsequence Rotation
6157	Codeforces 1370D: Odd-Even Subsequence
6156	Codeforces 1370C: Number Game
6155	Codeforces 1370B: GCD Compression
6154	Codeforces 1370A: Maximum GCD
6153	Codeforces 1369F: BareLee
6152	Codeforces 1369E: DeadLee

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

6201

Codeforces 1379E: Inverse Genealogy

6200

Codeforces 1379D: New Passenger Trams

6199

Codeforces 1379C: Choosing flowers

6198

Codeforces 1379B: Dubious Cyrpto

6197

Codeforces 1379A: Acacius and String

6196