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)
8151	Codeforces 1743A: Password
8150	Codeforces 1742G: Orray
8149	Codeforces 1742F: Smaller
8148	Codeforces 1742E: Scuza
8147	Codeforces 1742D: Coprime
8146	Codeforces 1742C: Stripes
8145	Codeforces 1742B: Increasing
8144	Codeforces 1742A: Sum
8143	Codeforces 1741G: Kirill and Company
8142	Codeforces 1741F: Multi-Colored Segments
8141	Codeforces 1741E: Sending a Sequence Over the Network
8140	Codeforces 1741D: Masha and a Beautiful Tree
8139	Codeforces 1741C: Minimize the Thickness
8138	Codeforces 1741B: Funny Permutation
8137	Codeforces 1741A: Compare T-Shirt Sizes
8136	Codeforces 1740I: Arranging Crystal Balls
8135	Codeforces 1740H: MEX Tree Manipulation
8134	Codeforces 1740G: Dangerous Laser Power
8133	Codeforces 1740F: Conditional Mix
8132	Codeforces 1740E: Hanging Hearts
8131	Codeforces 1740D: Knowledge Cards
8130	Codeforces 1740C: Bricks and Bags
8129	Codeforces 1740B: Jumbo Extra Cheese 2
8128	Codeforces 1740A: Factorise N+M
8127	Codeforces 1739F: Keyboard Design
8126	Codeforces 1739E: Cleaning Robot
8125	Codeforces 1739D: Reset K Edges
8124	Codeforces 1739C: Card Game
8123	Codeforces 1739B: Array Recovery
8122	Codeforces 1739A: Immobile Knight
8121	Codeforces 1738H: Palindrome Addicts
8120	Codeforces 1738G: Anti-Increasing Addicts
8119	Codeforces 1738F: Connectivity Addicts
8118	Codeforces 1738E: Balance Addicts
8117	Codeforces 1738D: Permutation Addicts
8116	Codeforces 1738C: Even Number Addicts
8115	Codeforces 1738B: Prefix Sum Addicts
8114	Codeforces 1738A: Glory Addicts
8113	Codeforces 1737G: Ela Takes Dancing Class
8112	Codeforces 1737F: Ela and Prime GCD
8111	Codeforces 1737E: Ela Goes Hiking
8110	Codeforces 1737D: Ela and the Wiring Wizard
8109	Codeforces 1737C: Ela and Crickets
8108	Codeforces 1737B: Ela's Fitness and the Luxury Number
8107	Codeforces 1737A: Ela Sorting Books
8106	Codeforces 1736E: Swap and Take
8105	Codeforces 1736D: Equal Binary Subsequences
8104	Codeforces 1736C2: Good Subarrays (Hard Version)
8103	Codeforces 1736C1: Good Subarrays (Easy Version)
8102	Codeforces 1736B: Playing with GCD

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

8151

Codeforces 1743A: Password

8150

Codeforces 1742G: Orray

8149

Codeforces 1742F: Smaller

8148

Codeforces 1742E: Scuza

8147

Codeforces 1742D: Coprime

8146