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)
11301	AtCoder ABC045: D. Snuke's Coloring
11300	AtCoder ABC045: C. Many Formulas
11299	AtCoder ARC060: F. Best Representation
11298	AtCoder ARC060: E. Tak and Hotels
11297	AtCoder ABC044: D. Digit Sum
11296	AtCoder ABC044: C. Tak and Cards
11295	AtCoder ARC059: F. Unhappy Hacking
11294	AtCoder ARC059: E. Children and Candies
11293	AtCoder ARC059: D. Unbalanced
11292	AtCoder ARC059: C. Be Together
11291	AtCoder ARC058: F. Iroha Loves Strings
11290	AtCoder ARC058: E. Iroha and Haiku
11289	AtCoder ARC058: D. Iroha and a Grid
11288	AtCoder ARC058: C. Iroha's Obsession
11287	AtCoder ARC057: D. 全域木
11286	AtCoder ARC057: C. 2乗根
11285	AtCoder ARC057: B. 高橋君ゲーム
11284	AtCoder ARC057: A. 2兆円
11283	AtCoder ARC056: D. サケノミ
11282	AtCoder ARC056: C. 部門分け
11281	AtCoder ARC056: B. 駐車場
11280	AtCoder ARC056: A. みんなでワイワイみかん
11279	AtCoder ARC055: D. 隠された等差数列
11278	AtCoder ARC055: C. ABCAC
11277	AtCoder ARC055: B. せんべい
11276	AtCoder ARC055: A. 数え上げ
11275	AtCoder ARC054: D. バブルソート
11274	AtCoder ARC054: C. 鯛焼き
11273	AtCoder ARC054: B. ムーアの法則
11272	AtCoder ARC054: A. 動く歩道
11271	AtCoder ARC053: D. 2 つの山札
11270	AtCoder ARC053: C. 魔法使い高橋君
11269	AtCoder ARC053: B. 回文分割
11268	AtCoder ARC053: A. ドミノ色塗り
11267	AtCoder ARC052: D. 9
11266	AtCoder ARC052: C. 高橋くんと不思議な道
11265	AtCoder ARC052: B. 円錐
11264	AtCoder ARC052: A. 何期生？
11263	AtCoder ARC051: D. 長方形
11262	AtCoder ARC051: C. 掛け算
11261	AtCoder ARC051: B. 互除法
11260	AtCoder ARC051: A. 塗り絵
11259	AtCoder ARC050: D. Suffix Concat
11258	AtCoder ARC050: C. LCM 111
11257	AtCoder ARC050: B. 花束
11256	AtCoder ARC050: A. 大文字と小文字
11255	AtCoder ARC049: D. すわっぷしまーす
11254	AtCoder ARC049: C. ぬりまーす
11253	AtCoder ARC049: B. 高橋ノルム君
11252	AtCoder ARC049: A. "強調"

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

11301

AtCoder ABC045: D. Snuke's Coloring

11300

AtCoder ABC045: C. Many Formulas

11299

AtCoder ARC060: F. Best Representation

11298

AtCoder ARC060: E. Tak and Hotels

11297

AtCoder ABC044: D. Digit Sum

11296