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)
24151	AtCoder ABC326: G. Unlock Achievement
24150	AtCoder ABC326: F. Robot Rotation
24149	AtCoder ABC326: E. Revenge of "The Salary of AtCoder Inc."
24148	AtCoder ABC326: D. ABC Puzzle
24147	AtCoder ABC326: C. Peak
24146	AtCoder ABC326: B. 326-like Numbers
24145	AtCoder ABC326: A. 2UP3DOWN
24144	Codeforces 1890B: Qingshan Loves Strings
24143	Codeforces 1890A: Doremy's Paint 3
24142	Codeforces 1889F: Doremy's Average Tree
24141	Codeforces 1889E: Doremy's Swapping Trees
24140	Codeforces 1889D: Game of Stacks
24139	Codeforces 1889C2: Doremy's Drying Plan (Hard Version)
24138	Codeforces 1889C1: Doremy's Drying Plan (Easy Version)
24137	Codeforces 1889B: Doremy's Connecting Plan
24136	Codeforces 1889A: Qingshan Loves Strings 2
24135	DMOJ Waterloo 2023 Fall E - Loose Goose
24134	DMOJ Waterloo 2023 Fall D - Reptilian Communism
24133	DMOJ Waterloo 2023 Fall C - Whitewater Rafting
24132	DMOJ Waterloo 2023 Fall B - Orb Tent
24131	DMOJ Waterloo 2023 Fall A - Black Frame
24130	DMOJ NOI '17 P4 - Game
24129	AtCoder TTPC2023: P. Bridge Elimination
24128	AtCoder TTPC2023: O. 2D Parentheses
24127	AtCoder TTPC2023: N. Bracket Sequestion
24126	AtCoder TTPC2023: M. Sum is Integer
24125	AtCoder TTPC2023: L. Next TTPC 3
24124	AtCoder TTPC2023: K. Dense Planting
24123	AtCoder TTPC2023: J. Set Construction
24122	AtCoder TTPC2023: I. T Tile Placement Counting
24121	AtCoder TTPC2023: H. 404 Chotto Found
24120	AtCoder TTPC2023: G. Cola
24119	AtCoder TTPC2023: F. N^a (log N)^b
24118	AtCoder TTPC2023: E. R-Connected Components
24117	AtCoder TTPC2023: D. Spacecraft
24116	AtCoder TTPC2023: C. Yet Another Simple Math Problem
24115	AtCoder TTPC2023: B. Almost Large
24114	AtCoder TTPC2023: A. Numerous Elimination
24113	AtCoder JOI2024YO1B: D. 繰り返し (Repetition)
24112	AtCoder JOI2024YO1B: C. 画数数え (Stroke Count)
24111	AtCoder JOI2024YO1B: B. 火曜日 (Tuesday)
24110	AtCoder JOI2024YO1B: A. 飴の袋詰め (Drops Packing)
24109	AtCoder ARC167: F. Tree Tree Tree
24108	AtCoder ARC167: E. One Square in a Triangle
24107	AtCoder ARC167: D. Good Permutation
24106	AtCoder ARC167: C. MST on Line++
24105	AtCoder ARC167: B. Product of Divisors
24104	AtCoder ARC167: A. Toasts for Breakfast Party
24103	AtCoder ARC166: F. Tangent Addition Formula
24102	AtCoder ARC166: E. Fizz Buzz Difference

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

24151

AtCoder ABC326: G. Unlock Achievement

24150

AtCoder ABC326: F. Robot Rotation

24149

AtCoder ABC326: E. Revenge of "The Salary of AtCoder Inc."

24148

AtCoder ABC326: D. ABC Puzzle

24147

AtCoder ABC326: C. Peak

24146