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)
12701	AtCoder IROHA2019-DAY2: H. 根室の巫女
12700	AtCoder IROHA2019-DAY2: G. 通学路
12699	AtCoder IROHA2019-DAY2: F. 総入れ替え
12698	AtCoder IROHA2019-DAY2: E. 連呼
12697	AtCoder IROHA2019-DAY2: D. 楽しすぎる家庭菜園
12696	AtCoder IROHA2019-DAY2: C. 陽気な妖姫
12695	AtCoder IROHA2019-DAY2: B. 河川敷の変態仮面
12694	AtCoder IROHA2019-DAY2: A. わたのはら
12693	AtCoder IROHA2019-DAY1: L. をあぷろぶれむ
12692	AtCoder IROHA2019-DAY1: K. ルーレット
12691	AtCoder IROHA2019-DAY1: J. ヌクレオチド
12690	AtCoder IROHA2019-DAY1: I. リスのお仕事
12689	AtCoder IROHA2019-DAY1: H. ちらし寿司
12688	AtCoder IROHA2019-DAY1: G. 友達以上恋人以下
12687	AtCoder IROHA2019-DAY1: F. Head of The Dragon
12686	AtCoder IROHA2019-DAY1: E. 放課後
12685	AtCoder IROHA2019-DAY1: D. 肉と肉のぶつかり合い
12684	AtCoder IROHA2019-DAY1: C. Halcyon
12683	AtCoder IROHA2019-DAY1: B. ローリング・老人と海
12682	AtCoder IROHA2019-DAY1: A. 一問目
12681	AtCoder INTRO-HEURISTICS: C. Incremental Scoring
12680	AtCoder INTRO-HEURISTICS: B. Scoring
12679	AtCoder INTRO-HEURISTICS: A. AtCoder Contest Scheduling
12678	AtCoder INDEEDNOW-QUALB: C. 木
12677	AtCoder INDEEDNOW-QUALB: D. 高橋くんと数列
12676	AtCoder INDEEDNOW-QUALB: B. 高橋くんと文字列操作
12675	AtCoder INDEEDNOW-QUALB: A. 高橋くんとマンハッタン
12674	AtCoder INDEEDNOW-QUALA: D. パズル
12673	AtCoder INDEEDNOW-QUALA: C. 説明会
12672	AtCoder INDEEDNOW-QUALA: B. Indeedなう！
12671	AtCoder INDEEDNOW-QUALA: A. 掛け算の筆算
12670	AtCoder INDEEDNOW-FINALB-OPEN: E. Line up!
12669	AtCoder INDEEDNOW-FINALB-OPEN: D. Game on a Grid
12668	AtCoder INDEEDNOW-FINALB-OPEN: C. Palindrome Concatenation
12667	AtCoder INDEEDNOW-FINALB-OPEN: B. How are you?
12666	AtCoder INDEEDNOW-FINALB-OPEN: A. Counting on a Triangle
12665	AtCoder INDEEDNOW-FINALA-OPEN: F. 就職活動
12664	AtCoder INDEEDNOW-FINALA-OPEN: E. Page Rank
12663	AtCoder INDEEDNOW-FINALA-OPEN: D. Longest Path
12662	AtCoder INDEEDNOW-FINALA-OPEN: C. Optimal Recommendations
12661	AtCoder INDEEDNOW-FINALA-OPEN: B. Office Ninja
12660	AtCoder INDEEDNOW-FINALA-OPEN: A. Table Tennis
12659	AtCoder IJPC2012PR: D. 分散 (Variance)
12658	AtCoder IJPC2012-1: C. 魔法の訓練 (Magical Training)
12657	AtCoder IJPC2012PR: C. 提出 (Submission)
12656	AtCoder IJPC2012-1: B. 銀メダル (Silver Medal)
12655	AtCoder IJPC2012PR: B. 合成数を倒せ (Prime Hazard)
12654	AtCoder IJPC2012-2: C. ポーター・テレ・ポーター (Porter-Tele-Porter)
12653	AtCoder IJPC2012-2: B. にひきのきつねとくらがりのめいろ (Two Foxes and the Dark Maze)
12652	AtCoder IJPC2012-2: A. 国際道迷いオリンピック(International Michimayoi Olympic)

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

12701

AtCoder IROHA2019-DAY2: H. 根室の巫女

12700

AtCoder IROHA2019-DAY2: G. 通学路

12699

AtCoder IROHA2019-DAY2: F. 総入れ替え

12698

AtCoder IROHA2019-DAY2: E. 連呼

12697

AtCoder IROHA2019-DAY2: D. 楽しすぎる家庭菜園

12696