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)
14501	AtCoder TKPPC: H. 私、木になります (I become a tree)
14500	AtCoder TKPPC: G. おおきなかずを作った (I made a huge number)
14499	AtCoder TKPPC: F. 吹奏楽部 (Brass Band)
14498	AtCoder TKPPC: E. 不可視境界線 (The Invisible Borderline)
14497	AtCoder TKPPC: D. サポーター (Supporter)
14496	AtCoder TKPPC: C. お姉ちゃんって呼んで (Call me sister)
14495	AtCoder TKPPC: B. 金髪の少女 (Blonde girls)
14494	AtCoder TKPPC: A. 足し算の宿題 (A + B Home work)
14493	AtCoder LANGUAGE-TEST-VER1: G. アルファベット探し
14492	AtCoder LANGUAGE-TEST-VER1: F. THE☆たこ焼き祭り2012
14491	AtCoder LANGUAGE-TEST-VER1: E. 平均値太郎の憂鬱
14490	AtCoder LANGUAGE-TEST-VER1: D. 超大型連休
14489	AtCoder LANGUAGE-TEST-VER1: C. おとぎの国の高橋君
14488	AtCoder LANGUAGE-TEST-VER1: B. 帰ってきた器物損壊！高橋君
14487	AtCoder LANGUAGE-TEST-VER1: A. センター採点
14486	AtCoder TESSOKU-BOOK: A26. Prime Check
14485	AtCoder TESSOKU-BOOK: A25. Number of Routes
14484	AtCoder TESSOKU-BOOK: A24. LIS
14483	AtCoder TESSOKU-BOOK: A23. All Free
14482	AtCoder TESSOKU-BOOK: A22. Sugoroku
14481	AtCoder TESSOKU-BOOK: A21. Block Game
14480	AtCoder TESSOKU-BOOK: A20. LCS
14479	AtCoder TESSOKU-BOOK: A19. Knapsack 1
14478	AtCoder TESSOKU-BOOK: A18. Subset Sum
14477	AtCoder TESSOKU-BOOK: A17. Dungeon 2
14476	AtCoder TESSOKU-BOOK: A16. Dungeon 1（※初版第 1 刷の B22 も同じ問題です）
14475	AtCoder TESSOKU-BOOK: A15. Compression
14474	AtCoder TESSOKU-BOOK: A14. Four Boxes
14473	AtCoder TESSOKU-BOOK: A13. Close Pairs
14472	AtCoder TESSOKU-BOOK: A12. Printer
14471	AtCoder TESSOKU-BOOK: A11. Binary Search 1
14470	AtCoder TESSOKU-BOOK: A10. Resort Hotel
14469	AtCoder TESSOKU-BOOK: A09. Winter in ALGO Kingdom
14468	AtCoder TESSOKU-BOOK: A08. Two Dimensional Sum
14467	AtCoder TESSOKU-BOOK: A07. Event Attendance
14466	AtCoder TESSOKU-BOOK: C20. Mayor's Challenge
14465	AtCoder TESSOKU-BOOK: C19. Gasoline Optimization Problem
14464	AtCoder TESSOKU-BOOK: C17. Strange Data Structure?
14463	AtCoder TESSOKU-BOOK: C16. Flights
14462	AtCoder TESSOKU-BOOK: C15. Many Meetings
14461	AtCoder TESSOKU-BOOK: C14. Commute Route
14460	AtCoder TESSOKU-BOOK: C13. Select 2
14459	AtCoder TESSOKU-BOOK: C12. Taro the Novel Writer
14458	AtCoder TESSOKU-BOOK: C11. Election
14457	AtCoder TESSOKU-BOOK: C10. A Long Grid
14456	AtCoder TESSOKU-BOOK: C08. ALGO4
14455	AtCoder TESSOKU-BOOK: C07. ALGO-MARKET
14454	AtCoder TESSOKU-BOOK: C06. Regular Graph
14453	AtCoder TESSOKU-BOOK: C05. Lucky Numbers
14452	AtCoder TESSOKU-BOOK: C04. Divisor Enumeration

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

14501

AtCoder TKPPC: H. 私、木になります (I become a tree)

14500

AtCoder TKPPC: G. おおきなかずを作った (I made a huge number)

14499

AtCoder TKPPC: F. 吹奏楽部 (Brass Band)

14498

AtCoder TKPPC: E. 不可視境界線 (The Invisible Borderline)

14497

AtCoder TKPPC: D. サポーター (Supporter)

14496