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)
14351	AtCoder TESSOKU-BOOK: A28. Blackboard
14350	AtCoder TESSOKU-BOOK: A01. The First Problem
14349	AtCoder TENKA1-2019: F. Banned X
14348	AtCoder TENKA1-2019: E. Polynomial Divisors
14347	AtCoder TENKA1-2019: D. Three Colors
14346	AtCoder TENKA1-2019: C. Stones
14345	AtCoder TENKA1-2019-BEGINNER: B. e* *****e e**e **e
14344	AtCoder TENKA1-2019-BEGINNER: A. On the Way
14343	AtCoder TENKA1-2018: F. Circular
14342	AtCoder TENKA1-2018: E. Equilateral
14341	AtCoder TENKA1-2018: D. Crossing
14340	AtCoder TENKA1-2018: C. Align
14339	AtCoder TENKA1-2018-BEGINNER: B. Exchange
14338	AtCoder TENKA1-2018-BEGINNER: A. Measure
14337	AtCoder TENKA1-2017: F. ModularPowerEquation!!
14336	AtCoder TENKA1-2017: E. CARtesian Coodinate
14335	AtCoder TENKA1-2017: D. IntegerotS
14334	AtCoder TENKA1-2017: C. 4/N
14333	AtCoder TENKA1-2017-BEGINNER: B. Different Distribution
14332	AtCoder TENKA1-2017-BEGINNER: A. Accepted...?
14331	AtCoder TENKA1-2016-QUALB: E. 天下一合体
14330	AtCoder TENKA1-2016-QUALB: D. 天下一数列にクエリを投げます
14329	AtCoder TENKA1-2016-QUALB: C. 天下一プログラマーコンテスト1999
14328	AtCoder TENKA1-2016-QUALB: B. 天下一魔力発電
14327	AtCoder TENKA1-2016-QUALB: A. 天下一合成関数
14326	AtCoder TENKA1-2016-QUALA: E. 無限グラフ
14325	AtCoder TENKA1-2016-QUALA: D. グラフィカルグラフ
14324	AtCoder TENKA1-2016-QUALA: C. 山田山本問題
14323	AtCoder TENKA1-2016-QUALA: B. PackDrop
14322	AtCoder TENKA1-2016-QUALA: A. 天下一プログラマーゲーム
14321	AtCoder TENKA1-2016-FINAL: F. Blind Purchase
14320	AtCoder TENKA1-2016-FINAL: E. 串焼きパーティ
14319	AtCoder TENKA1-2016-FINAL: D. 右往左往
14318	AtCoder TENKA1-2016-FINAL: C. たんごたくさん
14317	AtCoder TENKA1-2016-FINAL: B. 今年の B 問題
14316	AtCoder TENKA1-2016-FINAL: A. 今年の A 問題
14315	AtCoder TENKA1-2015-QUALB: E. 天下一演算
14314	AtCoder TENKA1-2015-QUALB: D. 天下一電卓英作文
14313	AtCoder TENKA1-2015-QUALB: C. 擬二等辺三角形
14312	AtCoder TENKA1-2015-QUALB: B. 天下一リテラル
14311	AtCoder TENKA1-2015-QUALB: A. 天下一プログラマーコンテスト1998
14310	AtCoder TENKA1-2015-QUALA: E. 天下一魔法使い
14309	AtCoder TENKA1-2015-QUALA: D. ハシポン
14308	AtCoder TENKA1-2015-QUALA: C. 天下一美術館
14307	AtCoder TENKA1-2015-QUALA: B. stepモード
14306	AtCoder TENKA1-2015-QUALA: A. 展開図プログラマーコンテスト
14305	AtCoder TENKA1-2015-FINAL: G. 天下一ゲーム
14304	AtCoder TENKA1-2015-FINAL: F. 根付き木のみさわさん
14303	AtCoder TENKA1-2015-FINAL: E. 天下一コップ
14302	AtCoder TENKA1-2015-FINAL: D. ほぼピタゴラスの三角形

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

14351

AtCoder TESSOKU-BOOK: A28. Blackboard

14350

AtCoder TESSOKU-BOOK: A01. The First Problem

14349

AtCoder TENKA1-2019: F. Banned X

14348

AtCoder TENKA1-2019: E. Polynomial Divisors

14347

AtCoder TENKA1-2019: D. Three Colors

14346