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)
4151	Codeforces 977A: Wrong Subtraction
4150	Codeforces 976F: Minimal k-covering
4149	Codeforces 976E: Well played!
4148	Codeforces 976D: Degree Set
4147	Codeforces 976C: Nested Segments
4146	Codeforces 976B: Lara Croft and the New Game
4145	Codeforces 976A: Minimum Binary Number
4144	Codeforces 975E: Hag's Khashba
4143	Codeforces 975D: Ghosts
4142	Codeforces 975C: Valhalla Siege
4141	Codeforces 975B: Mancala
4140	Codeforces 975A: Aramic script
4139	Codeforces 967B: Watering System
4138	Codeforces 967A: Mind the Gap
4137	Codeforces 965E: Short Code
4136	Codeforces 965D: Single-use Stones
4135	Codeforces 965C: Greedy Arkady
4134	Codeforces 965B: Battleship
4133	Codeforces 965A: Paper Airplanes
4132	Codeforces 964B: Messages
4131	Codeforces 964A: Splits
4130	Codeforces 963E: Circles of Waiting
4129	Codeforces 963D: Frequency of String
4128	Codeforces 963C: Cutting Rectangle
4127	Codeforces 963B: Destruction of a Tree
4126	Codeforces 963A: Alternating Sum
4125	Codeforces 962G: Visible Black Areas
4124	Codeforces 962F: Simple Cycles Edges
4123	Codeforces 962E: Byteland, Berland and Disputed Cities
4122	Codeforces 962D: Merge Equals
4121	Codeforces 962C: Make a Square
4120	Codeforces 962B: Students in Railway Carriage
4119	Codeforces 962A: Equator
4118	Codeforces 961G: Partitions
4117	Codeforces 961F: k-substrings
4116	Codeforces 961E: Tufurama
4115	Codeforces 961D: Pair Of Lines
4114	Codeforces 961C: Chessboard
4113	Codeforces 961B: Lecture Sleep
4112	Codeforces 961A: Tetris
4111	Codeforces 960H: Santa's Gift
4110	Codeforces 960G: Bandit Blues
4109	Codeforces 960F: Pathwalks
4108	Codeforces 960E: Alternating Tree
4107	Codeforces 960D: Full Binary Tree Queries
4106	Codeforces 960C: Subsequence Counting
4105	Codeforces 960B: Minimize the error
4104	Codeforces 960A: Check the string
4103	Codeforces 959F: Mahmoud and Ehab and yet another xor task
4102	Codeforces 959E: Mahmoud and Ehab and the xor-MST

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

4151

Codeforces 977A: Wrong Subtraction

4150

Codeforces 976F: Minimal k-covering

4149

Codeforces 976E: Well played!

4148

Codeforces 976D: Degree Set

4147

Codeforces 976C: Nested Segments

4146