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)
11101	AtCoder ARC011: B. ルイス・キャロルの記憶術
11100	AtCoder ARC011: A. 鉛筆リサイクルの新技術
11099	AtCoder ARC010: D. 情報伝播
11098	AtCoder ARC010: C. 積み上げパズル
11097	AtCoder ARC010: B. 超大型連休
11096	AtCoder ARC010: A. 名刺交換
11095	AtCoder ARC009: D. 覚醒ノ高橋君
11094	AtCoder ARC009: C. 高橋君、24歳
11093	AtCoder ARC009: B. おとぎの国の高橋君
11092	AtCoder ARC009: A. 元気にお使い！高橋君
11091	AtCoder ARC008: D. タコヤキオイシクナール
11090	AtCoder ARC008: C. THE☆たこ焼き祭り2012
11089	AtCoder ARC008: B. 謎のたこ焼きおじさん
11088	AtCoder ARC008: A. たこ焼き買えるかな？
11087	AtCoder ARC007: D. 破れた宿題
11086	AtCoder ARC007: C. 節約生活
11085	AtCoder ARC007: B. 迷子のCDケース
11084	AtCoder ARC007: A. 帰ってきた器物損壊！高橋君
11083	AtCoder ARC006: D. アルファベット探し
11082	AtCoder ARC006: C. 積み重ね
11081	AtCoder ARC006: B. あみだくじ
11080	AtCoder ARC006: A. 宝くじ
11079	AtCoder ARC005: D. 連射王高橋君
11078	AtCoder ARC005: C. 器物損壊！高橋君
11077	AtCoder ARC005: B. P-CASカードと高橋君
11076	AtCoder ARC005: A. 大好き高橋君
11075	AtCoder ARC004: D. 表現の自由 ( Freedom of expression )
11074	AtCoder ARC004: C. 平均値太郎の憂鬱 ( The melancholy of Taro Heikinchi )
11073	AtCoder ARC004: B. 2点間距離の最大と最小 ( Maximum and Minimum )
11072	AtCoder ARC004: A. 2点間距離の最大値 ( The longest distance )
11071	AtCoder ARC003: D. シャッフル席替え
11070	AtCoder ARC003: C. 暗闇帰り道
11069	AtCoder ARC003: B. さかさま辞書
11068	AtCoder ARC003: A. GPA計算
11067	AtCoder ARC002: D. ボードゲーム
11066	AtCoder ARC002: C. コマンド入力
11065	AtCoder ARC002: B. 割り切れる日付
11064	AtCoder ARC002: A. うるう年
11063	AtCoder ARC001: D. レースゲーム
11062	AtCoder ARC001: C. パズルのお手伝い
11061	AtCoder ARC001: B. リモコン
11060	AtCoder ARC001: A. センター採点
11059	AtCoder JOIOPEN2012C: C. Mansion
11058	AtCoder JOIOPEN2012C: B. Jumps
11057	AtCoder JOIOPEN2012C: A. Code
11056	AtCoder APC001: J. Rectangles
11055	AtCoder APC001: I. Simple APSP Problem
11054	AtCoder APC001: H. Generalized Insertion Sort
11053	AtCoder APC001: G. Colorful Doors
11052	AtCoder APC001: F. XOR Tree

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

11101

AtCoder ARC011: B. ルイス・キャロルの記憶術

11100

AtCoder ARC011: A. 鉛筆リサイクルの新技術

11099

AtCoder ARC010: D. 情報伝播

11098

AtCoder ARC010: C. 積み上げパズル

11097

AtCoder ARC010: B. 超大型連休

11096