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)
13701	AtCoder NYC2015: K. チーム戦
13700	AtCoder NYC2015: J. ランダムウォーク
13699	AtCoder NYC2015: A. 2015
13698	AtCoder NOMURA2020: F. Sorting Game
13697	AtCoder NOMURA2020: E. Binary Programming
13696	AtCoder NOMURA2020: D. Urban Planning
13695	AtCoder NOMURA2020: C. Folia
13694	AtCoder NOMURA2020: B. Postdocs
13693	AtCoder NOMURA2020: A. Study Scheduling
13692	AtCoder NJPC2017: H. 白黒ツリー
13691	AtCoder NJPC2017: G. 交換法則
13690	AtCoder NJPC2017: F. ダブルス
13689	AtCoder NJPC2017: E. 限界集落
13688	AtCoder NJPC2017: D. NMパズル
13687	AtCoder NJPC2017: C. ハードル走
13686	AtCoder NJPC2017: B. 格子グラフ
13685	AtCoder NJPC2017: A. 入力フォーム
13684	AtCoder NIKKEI2019-EX: H. 8^kゲーム
13683	AtCoder NIKKEI2019-EX: G. 回文スコア
13682	AtCoder NIKKEI2019-EX: E. スーパーFizzBuzz
13681	AtCoder NIKKEI2019-EX: F. コラッツ問題
13680	AtCoder NIKKEI2019-EX: D. 辞書順最小の数
13679	AtCoder NIKKEI2019-EX: C. 11で割った余りの計算方法
13678	AtCoder NIKKEI2019-EX: B. 二乗
13677	AtCoder NIKKEI2019-EX: A. Prefix Array
13676	AtCoder NIKKEI2019-QUAL: F. Jewels
13675	AtCoder NIKKEI2019-QUAL: E. Weights on Vertices and Edges
13674	AtCoder NIKKEI2019-QUAL: D. Restore the Tree
13673	AtCoder NIKKEI2019-QUAL: C. Different Strokes
13672	AtCoder NIKKEI2019-QUAL: B. Touitsu
13671	AtCoder NIKKEI2019-QUAL: A. Subscribers
13670	AtCoder NIKKEI2019-FINAL: H. Homework Scheduling
13669	AtCoder NIKKEI2019-FINAL: G. Greatest Journey
13668	AtCoder NIKKEI2019-FINAL: F. Flights
13667	AtCoder NIKKEI2019-FINAL: E. Erasure
13666	AtCoder NIKKEI2019-FINAL: D. Deforestation
13665	AtCoder NIKKEI2019-FINAL: C. Come Together
13664	AtCoder NIKKEI2019-FINAL: B. Big Integers
13663	AtCoder NIKKEI2019-FINAL: A. Abundant Resources
13662	AtCoder NIKKEI2019-2-QUAL: F. Mirror Frame
13661	AtCoder NIKKEI2019-2-QUAL: E. Non-triangular Triplets
13660	AtCoder NIKKEI2019-2-QUAL: D. Shortest Path on a Line
13659	AtCoder NIKKEI2019-2-QUAL: C. Swaps
13658	AtCoder NIKKEI2019-2-QUAL: B. Counting of Trees
13657	AtCoder NIKKEI2019-2-QUAL: A. Sum of Two Integers
13656	AtCoder NIKKEI2019-2-FINAL: H. 逆にする関数
13655	AtCoder NIKKEI2019-2-FINAL: G. Road Trip
13654	AtCoder NIKKEI2019-2-FINAL: F. Jumping over 2
13653	AtCoder NIKKEI2019-2-FINAL: E. Notorious B.I.T.
13652	AtCoder NIKKEI2019-2-FINAL: D. 木、

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

13701

AtCoder NYC2015: K. チーム戦

13700

AtCoder NYC2015: J. ランダムウォーク

13699

AtCoder NYC2015: A. 2015

13698

AtCoder NOMURA2020: F. Sorting Game

13697

AtCoder NOMURA2020: E. Binary Programming

13696