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)
14251	AtCoder TDPC: N. 木
14250	AtCoder TDPC: C. トーナメント
14249	AtCoder TDPC: K. ターゲット
14248	AtCoder TDPC: O. 文字列
14247	AtCoder TDPC: F. 準急
14246	AtCoder TDPC: E. 数
14245	AtCoder TDPC: G. 辞書順
14244	AtCoder TDPC: H. ナップザック
14243	AtCoder TDPC: I. イウィ
14242	AtCoder TDPC: M. 家
14241	AtCoder TDPC: S. マス目
14240	AtCoder TDPC: R. グラフ
14239	AtCoder TDPC: B. ゲーム
14238	AtCoder TDPC: T. フィボナッチ
14237	AtCoder TDPC: P. うなぎ
14236	AtCoder TDPC: D. サイコロ
14235	AtCoder TDPC: A. コンテスト
14234	AtCoder TDPC: Q. 連結
14233	AtCoder TDPC: L. 猫
14232	AtCoder TDPC: J. ボール
14231	AtCoder SUMMERFES2018-DIV1: J. 楽しい結界作り (Making Barriers Is Fun)
14230	AtCoder SUMMERFES2018-DIV1: I. うっかり者のニム (Careless Nim)
14229	AtCoder SUMMERFES2018-DIV1: H. 圧縮おみくじ (Compressed Omikuji)
14228	AtCoder SUMMERFES2018-DIV1: G. 屋台衝突 (Food Stall Collision)
14227	AtCoder SUMMERFES2018-DIV1: F. 冪冪ゲーム (Powerful Fever!)
14226	AtCoder SUMMERFES2018-DIV1: E. 石積み (Pyramid Piling)
14225	AtCoder SUMMERFES2018-DIV1: D. 木からパスへ (Tree--->path)
14224	AtCoder SUMMERFES2018-DIV2: C. 整数占い (Uranai Integer)
14223	AtCoder SUMMERFES2018-DIV2: B. 太鼓の名人 (Taiko Expert)
14222	AtCoder SUMMERFES2018-DIV2: A. 夏祭り会議 (Summer Festival Meeting)
14221	AtCoder SUMITRUST2019: F. Interval Running
14220	AtCoder SUMITRUST2019: E. Colorful Hats 2
14219	AtCoder SUMITRUST2019: D. Lucky PIN
14218	AtCoder SUMITRUST2019: C. 100 to 105
14217	AtCoder SUMITRUST2019: B. Tax Rate
14216	AtCoder SUMITRUST2019: A. November 30
14215	AtCoder STAGE0-2021: A. Patrolling
14214	AtCoder SOUNDHOUND2018-SUMMER-QUAL: E. + Graph
14213	AtCoder SOUNDHOUND2018-SUMMER-QUAL: D. Saving Snuuk
14212	AtCoder SOUNDHOUND2018-SUMMER-QUAL: C. Ordinary Beauty
14211	AtCoder SOUNDHOUND2018-SUMMER-QUAL: B. Acrostic
14210	AtCoder SOUNDHOUND2018-SUMMER-QUAL: A. F
14209	AtCoder SOUNDHOUND2018-SUMMER-FINAL: E. Hash Swapping
14208	AtCoder SOUNDHOUND2018-SUMMER-FINAL: D. Propagating Edges
14207	AtCoder SOUNDHOUND2018-SUMMER-FINAL: C. Not Too Close
14206	AtCoder SOUNDHOUND2018-SUMMER-FINAL: B. Neutralize
14205	AtCoder SOUNDHOUND2018-SUMMER-FINAL: A. Feel the Beat
14204	AtCoder SOUNDHOUND2018: E. カッコ列
14203	AtCoder SOUNDHOUND2018: D. 建物
14202	AtCoder SOUNDHOUND2018: C. 広告

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

14251

AtCoder TDPC: N. 木

14250

AtCoder TDPC: C. トーナメント

14249

AtCoder TDPC: K. ターゲット

14248

AtCoder TDPC: O. 文字列

14247

AtCoder TDPC: F. 準急

14246