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)
24051	Codeforces 1881G: Anya and the Mysterious String
24050	Codeforces 1881F: Minimum Maximum Distance
24049	Codeforces 1881E: Block Sequence
24048	Codeforces 1881D: Divide and Equalize
24047	Codeforces 1881C: Perfect Square
24046	Codeforces 1881B: Three Threadlets
24045	Codeforces 1881A: Don't Try to Count
24044	Codeforces 1877C: Joyboard
24043	Codeforces 1877A: Goals of Victory
24042	Codeforces 1876G: Clubstep
24041	Codeforces 1876F: Indefinite Clownfish
24040	Codeforces 1876E: Ball-Stackable
24039	Codeforces 1876D: Lexichromatography
24038	Codeforces 1876C: Autosynthesis
24037	Codeforces 1876B: Effects of Anti Pimples
24036	Codeforces 1876A: Helmets in Night Light
24035	AtCoder JSC2023-FINAL: G. Fusion
24034	AtCoder JSC2023-FINAL: F. Adjacent Binomial Coefficients
24033	AtCoder JSC2023-FINAL: E. Min Subtraction
24032	AtCoder JSC2023-FINAL: D. Two Xor
24031	AtCoder JSC2023-FINAL: C. Power Convergence
24030	AtCoder JSC2023-FINAL: B. Max Degree Sum
24029	AtCoder JSC2023-FINAL: A. Apple Addiction
24028	AtCoder JOI2024YO1A: D. 現れている数字 (Appearing Numbers)
24027	AtCoder JOI2024YO1A: C. ハミング距離 (Hamming Distance)
24026	AtCoder JOI2024YO1A: B. 和の判定 (Sum Checker)
24025	AtCoder JOI2024YO1A: A. 果物 (Fruit)
24024	AtCoder AHC024: A. Topological Map
24023	AtCoder ABC322: G. Two Kinds of Base
24022	AtCoder ABC322: F. Vacation Query
24021	AtCoder ABC322: E. Product Development
24020	AtCoder ABC322: D. Polyomino
24019	AtCoder ABC322: C. Festival
24018	AtCoder ABC322: B. Prefix and Suffix
24017	AtCoder ABC322: A. First ABC 2
24016	AtCoder ABC321: G. Electric Circuit
24015	AtCoder ABC321: F. #(subset sum = K) with Add and Erase
24014	AtCoder ABC321: E. Complete Binary Tree
24013	AtCoder ABC321: D. Set Menu
24012	AtCoder ABC321: C. 321-like Searcher
24011	AtCoder ABC321: B. Cutoff
24010	AtCoder ABC321: A. 321-like Checker
24009	Codeforces 1882E2: Two Permutations (Hard Version)
24008	Codeforces 1882E1: Two Permutations (Easy Version)
24007	Codeforces 1882D: Tree XOR
24006	Codeforces 1882C: Card Game
24005	Codeforces 1882B: Sets and Union
24004	Codeforces 1882A: Increasing Sequence
24003	Codeforces 1879F: Last Man Standing
24002	Codeforces 1879E: Interactive Game with Coloring

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

24051

Codeforces 1881G: Anya and the Mysterious String

24050

Codeforces 1881F: Minimum Maximum Distance

24049

Codeforces 1881E: Block Sequence

24048

Codeforces 1881D: Divide and Equalize

24047

Codeforces 1881C: Perfect Square

24046