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)
9851	AtCoder ABC218: C. Shapes
9850	AtCoder ABC218: B. qwerty
9849	AtCoder ABC218: A. Weather Forecast
9848	AtCoder ABC217: H. Snuketoon
9847	AtCoder ABC217: G. Groups
9846	AtCoder ABC217: F. Make Pair
9845	AtCoder ABC217: E. Sorting Queries
9844	AtCoder ABC217: D. Cutting Woods
9843	AtCoder ABC217: C. Inverse of Permutation
9842	AtCoder ABC217: B. AtCoder Quiz
9841	AtCoder ABC217: A. Lexicographic Order
9840	AtCoder ABC216: H. Random Robots
9839	AtCoder ABC216: G. 01Sequence
9838	AtCoder ABC216: F. Max Sum Counting
9837	AtCoder ABC216: E. Amusement Park
9836	AtCoder ABC216: D. Pair of Balls
9835	AtCoder ABC216: C. Many Balls
9834	AtCoder ABC216: B. Same Name
9833	AtCoder ABC216: A. Signed Difficulty
9832	AtCoder ABC215: H. Cabbage Master
9831	AtCoder ABC215: G. Colorful Candies 2
9830	AtCoder ABC215: F. Dist Max 2
9829	AtCoder ABC215: E. Chain Contestant
9828	AtCoder ABC215: D. Coprime 2
9827	AtCoder ABC215: C. One More aab aba baa
9826	AtCoder ABC215: B. log2(N)
9825	AtCoder ABC215: A. Your First Judge
9824	AtCoder ABC214: H. Collecting
9823	AtCoder ABC214: G. Three Permutations
9822	AtCoder ABC214: F. Substrings
9821	AtCoder ABC214: E. Packing Under Range Regulations
9820	AtCoder ABC214: D. Sum of Maximum Weights
9819	AtCoder ABC214: C. Distribution
9818	AtCoder ABC214: B. How many?
9817	AtCoder ABC214: A. New Generation ABC
9816	AtCoder ABC213: H. Stroll
9815	AtCoder ABC213: G. Connectivity 2
9814	AtCoder ABC213: F. Common Prefixes
9813	AtCoder ABC213: E. Stronger Takahashi
9812	AtCoder ABC213: D. Takahashi Tour
9811	AtCoder ABC213: C. Reorder Cards
9810	AtCoder ABC213: B. Booby Prize
9809	AtCoder ABC213: A. Bitwise Exclusive Or
9808	AtCoder ABC212: H. Nim Counting
9807	AtCoder ABC212: G. Power Pair
9806	AtCoder ABC212: F. Greedy Takahashi
9805	AtCoder ABC212: E. Safety Journey
9804	AtCoder ABC212: D. Querying Multiset
9803	AtCoder ABC212: C. Min Difference
9802	AtCoder ABC212: B. Weak Password

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

9851

AtCoder ABC218: C. Shapes

9850

AtCoder ABC218: B. qwerty

9849

AtCoder ABC218: A. Weather Forecast

9848

AtCoder ABC217: H. Snuketoon

9847

AtCoder ABC217: G. Groups

9846