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)
14101	AtCoder RCO-CONTEST-2018-QUAL: A. ゲーム実況者Xの挑戦
14100	AtCoder RCO-CONTEST-2018-FINAL: B. くるくる寿司
14099	AtCoder RCO-CONTEST-2018-FINAL: A. ぐるぐる庭園
14098	AtCoder RCO-CONTEST-2017-QUAL: B. Food Collector
14097	AtCoder RCO-CONTEST-2017-QUAL: A. Multiple Pieces
14096	AtCoder RCO-CONTEST-2017-FINAL: B. 日本橋大渋滞
14095	AtCoder RCO-CONTEST-2017-FINAL: A. 石油王Xの憂鬱
14094	AtCoder RCL-CONTEST-2021-LONG: A. Farm King X
14093	AtCoder RCL-CONTEST-2021: B. マッサージチェア2021
14092	AtCoder RCL-CONTEST-2021: A. 魔法使いXの戦い
14091	AtCoder RCL-CONTEST-2020-QUAL: B. イラストレーターXと不思議なペン
14090	AtCoder RCL-CONTEST-2020-QUAL: A. ゲーマーXとモノス大会
14089	AtCoder RCL-CONTEST-2020-FINAL: B. ハイパーお掃除ロボット
14088	AtCoder RCL-CONTEST-2020-FINAL: A. ハイパー覆面すごろく
14087	AtCoder QUPC2018: J. Repeat Strings
14086	AtCoder QUPC2018: I. Buffalo
14085	AtCoder QUPC2018: H. ukuku
14084	AtCoder QUPC2018: G. Tapu & Tapi 2
14083	AtCoder QUPC2018: F. Team Making
14082	AtCoder QUPC2018: E. Treeone
14081	AtCoder QUPC2018: D. Novelist
14080	AtCoder QUPC2018: C. Ito Campus
14079	AtCoder QUPC2018: B. Tapu & Tapi
14078	AtCoder QUPC2018: A. QUPC
14077	AtCoder QUPC2014: H. お風呂は気持ちいい
14076	AtCoder QUPC2014: G. 立ち入り禁止区域
14075	AtCoder QUPC2014: F. 設備移転
14074	AtCoder QUPC2014: E. 捕獲
14073	AtCoder QUPC2014: D. 切符分割
14072	AtCoder QUPC2014: C. 案内所
14071	AtCoder QUPC2014: B. 元素の系統名
14070	AtCoder QUPC2014: A. 成績判定
14069	AtCoder ABS: PracticeA. Welcome to AtCoder
14068	AtCoder PRACTICE2: L. Lazy Segment Tree
14067	AtCoder PRACTICE2: K. Range Affine Range Sum
14066	AtCoder PRACTICE2: J. Segment Tree
14065	AtCoder PRACTICE2: I. Number of Substrings
14064	AtCoder PRACTICE2: H. Two SAT
14063	AtCoder PRACTICE2: G. SCC
14062	AtCoder PRACTICE2: F. Convolution
14061	AtCoder PRACTICE2: E. MinCostFlow
14060	AtCoder PRACTICE2: D. Maxflow
14059	AtCoder PRACTICE2: C. Floor Sum
14058	AtCoder PRACTICE2: B. Fenwick Tree
14057	AtCoder PRACTICE2: A. Disjoint Set Union
14056	AtCoder PAST202303-OPEN: O. 区間ソートクエリ
14055	AtCoder PAST202303-OPEN: N. ゴミ出し
14054	AtCoder PAST202303-OPEN: M. お片付け
14053	AtCoder PAST202303-OPEN: L. 順位表
14052	AtCoder PAST202303-OPEN: K. 金貨と袋のゲーム

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

14101

AtCoder RCO-CONTEST-2018-QUAL: A. ゲーム実況者Xの挑戦

14100

AtCoder RCO-CONTEST-2018-FINAL: B. くるくる寿司

14099

AtCoder RCO-CONTEST-2018-FINAL: A. ぐるぐる庭園

14098

AtCoder RCO-CONTEST-2017-QUAL: B. Food Collector

14097

AtCoder RCO-CONTEST-2017-QUAL: A. Multiple Pieces

14096