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)
14151	AtCoder S8PC-2: D. 2016
14150	AtCoder S8PC-2: C. 何通りの分割方法がある？
14149	AtCoder S8PC-2: B. Division 2
14148	AtCoder S8PC-2: A. IOI列車で行こう2
14147	AtCoder S8PC-1: H. 3人の昼食 (The Lunch)
14146	AtCoder S8PC-1: G. Revenge of Traveling Salesman Problem
14145	AtCoder S8PC-1: F. square1001の好きな回文数 (square1001's Favorite Palindrome)
14144	AtCoder S8PC-1: E. 散歩 (E869120 and Path Length)
14143	AtCoder S8PC-1: D. square1001の通学経路 (square1001's School Road)
14142	AtCoder S8PC-1: C. お金の街 (The Money Town)
14141	AtCoder S8PC-1: B. ケーキ・カッティング (Cake Cutting)
14140	AtCoder S8PC-1: A. E869120列車 (E869120 Trains)
14139	AtCoder CF16-RELAY-OPEN: K. Problem on Tree
14138	AtCoder CF16-RELAY-OPEN: J. Connected Checkerboard
14137	AtCoder CF16-RELAY-OPEN: I. 3y3s Challenge
14136	AtCoder CF16-RELAY-OPEN: H. Early Bird
14135	AtCoder CF16-RELAY-OPEN: G. Magician
14134	AtCoder CF16-RELAY-OPEN: F. Trichotomy
14133	AtCoder CF16-RELAY-OPEN: E. Segment on Grid Paper
14132	AtCoder CF16-RELAY-OPEN: D. Magic Square 2
14131	AtCoder CF16-RELAY-OPEN: C. Kode Festival
14130	AtCoder CF16-RELAY-OPEN: B. Mirror String
14129	AtCoder CF16-RELAY-OPEN: A. Equivalent Resistance
14128	AtCoder CF17-RELAY-OPEN: J. Indifferent
14127	AtCoder CF17-RELAY-OPEN: I. Nice to Meet You
14126	AtCoder CF17-RELAY-OPEN: H. Akashic Records
14125	AtCoder CF17-RELAY-OPEN: G. Coinage
14124	AtCoder CF17-RELAY-OPEN: F. Capture
14123	AtCoder CF17-RELAY-OPEN: E. White and Blue
14122	AtCoder CF17-RELAY-OPEN: D. Shock
14121	AtCoder CF17-RELAY-OPEN: C. Garden
14120	AtCoder CF17-RELAY-OPEN: B. Evergrowing Tree
14119	AtCoder CF17-RELAY-OPEN: A. Kaiden
14118	AtCoder CF18-RELAY-OPEN: J. 健康診断
14117	AtCoder CF18-RELAY-OPEN: I. 一円を笑う者は一円に泣く
14116	AtCoder CF18-RELAY-OPEN: H. 最悪のバス停決定戦
14115	AtCoder CF18-RELAY-OPEN: G. バス停と凸包
14114	AtCoder CF18-RELAY-OPEN: F. バス旅行
14113	AtCoder CF18-RELAY-OPEN: E. 狼と狐
14112	AtCoder CF18-RELAY-OPEN: D. 数直線
14111	AtCoder CF18-RELAY-OPEN: C. 積まれた本
14110	AtCoder CF18-RELAY-OPEN: B. ロボット
14109	AtCoder CF18-RELAY-OPEN: A. カレンダー
14108	AtCoder RECRUIT-PROGRAMING-CONTEST-PRACTICE: B. ブロック並べ
14107	AtCoder RECRUIT-PROGRAMING-CONTEST-PRACTICE: A. ババ抜き
14106	AtCoder RCO-CONTEST-2019-QUAL: B. ファーマーXの収穫計画
14105	AtCoder RCO-CONTEST-2019-QUAL: A. ツーリストXの旅行計画
14104	AtCoder RCO-CONTEST-2019-FINAL: B. まわしてそろえる
14103	AtCoder RCO-CONTEST-2019-FINAL: A. めくってそろえる
14102	AtCoder RCO-CONTEST-2018-QUAL: B. ゲーム実況者Xのデフラグ

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

14151

AtCoder S8PC-2: D. 2016

14150

AtCoder S8PC-2: C. 何通りの分割方法がある？

14149

AtCoder S8PC-2: B. Division 2

14148

AtCoder S8PC-2: A. IOI列車で行こう2

14147

AtCoder S8PC-1: H. 3人の昼食 (The Lunch)

14146