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)
12301	AtCoder DP: I. Coins
12300	AtCoder DP: H. Grid 1
12299	AtCoder DP: G. Longest Path
12298	AtCoder DP: F. LCS
12297	AtCoder DP: E. Knapsack 2
12296	AtCoder DP: D. Knapsack 1
12295	AtCoder DP: C. Vacation
12294	AtCoder DP: B. Frog 2
12293	AtCoder DP: A. Frog 1
12292	AtCoder DONUTS-LIVE2014: E. お菓子やさん
12291	AtCoder DONUTS-LIVE2014: D. サバゲー
12290	AtCoder DONUTS-LIVE2014: C. ソーシャルゲーム
12289	AtCoder DONUTS-LIVE2014: B. 7th
12288	AtCoder DONUTS-LIVE2014: A. 勤怠管理
12287	AtCoder DONUTS-2015: D. ドーナツの箱詰め
12286	AtCoder DONUTS-2015: C. 行列のできるドーナツ屋
12285	AtCoder DONUTS-2015: B. Tokyo 7th シスターズ
12284	AtCoder DONUTS-2015: A. ドーナツの体積
12283	AtCoder DIVERTA2019: F. Edge Ordering
12282	AtCoder DIVERTA2019: E. XOR Partitioning
12281	AtCoder DIVERTA2019: D. DivRem Number
12280	AtCoder DIVERTA2019: C. AB Substrings
12279	AtCoder DIVERTA2019: B. RGB Boxes
12278	AtCoder DIVERTA2019: A. Consecutive Integers
12277	AtCoder DIVERTA2019-2: F. Diverta City
12276	AtCoder DIVERTA2019-2: E. Balanced Piles
12275	AtCoder DIVERTA2019-2: D. Squirrel Merchant
12274	AtCoder DIVERTA2019-2: C. Successive Subtraction
12273	AtCoder DIVERTA2019-2: B. Picking Up
12272	AtCoder DIVERTA2019-2: A. Ball Distribution
12271	AtCoder DISCOVERY2016-QUAL: D. DDPC特別ビュッフェ
12270	AtCoder DISCOVERY2016-QUAL: C. アメージングな文字列は、きみが作る！
12269	AtCoder DISCOVERY2016-QUAL: B. ディスコ社内ツアー
12268	AtCoder DISCOVERY2016-QUAL: A. DISCO presents ディスカバリーチャンネルプログラミングコンテスト 2016
12267	AtCoder DISCOVERY2016-FINAL: E. アメージングな二分探索木は、きみが作る！
12266	AtCoder DISCOVERY2016-FINAL: D. ディスコ社内ツアーⅡ
12265	AtCoder DISCOVERY2016-FINAL: C. 特別講演「括弧列と塗り分け」
12264	AtCoder DISCOVERY2016-FINAL: B. DDPC特別ビュッフェⅡ
12263	AtCoder DISCOVERY2016-FINAL: A. DISCO presents ディスカバリーチャンネルプログラミングコンテスト 2016 Ⅱ
12262	AtCoder DIGITALARTS2012: C. Chokutter
12261	AtCoder DIGITALARTS2012: B. Password
12260	AtCoder DIGITALARTS2012: A. C-Filter
12259	AtCoder ATC001: A. 深さ優先探索
12258	AtCoder DDCC2016-QUAL: D. 道路網
12257	AtCoder DDCC2016-QUAL: C. ロト2
12256	AtCoder DDCC2016-QUAL: B. ステップカット
12255	AtCoder DDCC2016-QUAL: A. SDカード
12254	AtCoder DDCC2016-FINAL: E. 根付き木とクエリ
12253	AtCoder DDCC2016-FINAL: D. シャツの部屋
12252	AtCoder DDCC2016-FINAL: C. 01文字列

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

12301

AtCoder DP: I. Coins

12300

AtCoder DP: H. Grid 1

12299

AtCoder DP: G. Longest Path

12298

AtCoder DP: F. LCS

12297

AtCoder DP: E. Knapsack 2

12296