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)
14551	AtCoder TKPPC4-2: L. 建物と魔女
14550	AtCoder TKPPC4-2: K. 時をかけるTMJN
14549	AtCoder TKPPC4-2: J. ドライブ旅行
14548	AtCoder TKPPC4-2: I. 互いに素でないペアを持つ N の約数の集合の個数を求めてください。
14547	AtCoder TKPPC4-2: H. 打鍵戦争
14546	AtCoder TKPPC4-2: G. 平均レーティング
14545	AtCoder TKPPC4-2: F. Segtree☆Magica
14544	AtCoder TKPPC4-2: E. 引きこもり
14543	AtCoder TKPPC4-2: D. 新入生歓迎数列 2
14542	AtCoder TKPPC4-2: C. Parity
14541	AtCoder TKPPC4-2: B. Stalker
14540	AtCoder TKPPC4-2: A. Jumping!!
14539	AtCoder TKPPC4-1: P. Flip Cards
14538	AtCoder TKPPC4-1: O. Height Changer
14537	AtCoder TKPPC4-1: N. multiple
14536	AtCoder TKPPC4-1: M. Pakenのうさぎ
14535	AtCoder TKPPC4-1: L. じゃんけん
14534	AtCoder TKPPC4-1: K. 天使と宿題
14533	AtCoder TKPPC4-1: J. school competition 2
14532	AtCoder TKPPC4-1: I. school competition 1
14531	AtCoder TKPPC4-1: H. don't be late
14530	AtCoder TKPPC4-1: G. バラバラ掛け算
14529	AtCoder TKPPC4-1: F. 不便な橋
14528	AtCoder TKPPC4-1: E. Osmium_1008と課題
14527	AtCoder TKPPC4-1: D. スキップ
14526	AtCoder TKPPC4-1: C. 異世界転生
14525	AtCoder TKPPC4-1: B. Long Long Ago
14524	AtCoder TKPPC4-1: A. ヘビがヘビー
14523	AtCoder TKPPC3: J. 円の重なり
14522	AtCoder TKPPC3: I. 王国と M 種類の店
14521	AtCoder TKPPC3: H. 新入生歓迎数列 - Hard
14520	AtCoder TKPPC3: G. パソコンの買い替え
14519	AtCoder TKPPC3: F. 天使とふすま
14518	AtCoder TKPPC3: E. デフレゲーム
14517	AtCoder TKPPC3: D. 巨大チェスボード
14516	AtCoder TKPPC3: C. 新入生歓迎数列 - Easy
14515	AtCoder TKPPC3: B. 鰻と忖度
14514	AtCoder TKPPC3: A. 時差
14513	AtCoder TKPPC2: J. 次のお仕事 (New Game)
14512	AtCoder TKPPC2: I. ボス（Boss）
14511	AtCoder TKPPC2: H. デバッグ（Debug）
14510	AtCoder TKPPC2: G. 貢物（Tribute）
14509	AtCoder TKPPC2: F. NPCの家 (NPC's House)
14508	AtCoder TKPPC2: E. 歩くNPCたち（Walking NPCs）
14507	AtCoder TKPPC2: D. エンブレム（Emblem）
14506	AtCoder TKPPC2: C. 有給休暇（Paid Vacation）
14505	AtCoder TKPPC2: B. 書き換え（Rewrite）
14504	AtCoder TKPPC2: A. 入社（Join the Company）
14503	AtCoder TKPPC: J. 仕事をしよう！ (Working!)
14502	AtCoder TKPPC: I. 重要証拠 (Important evidence)

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

14551

AtCoder TKPPC4-2: L. 建物と魔女

14550

AtCoder TKPPC4-2: K. 時をかけるTMJN

14549

AtCoder TKPPC4-2: J. ドライブ旅行

14548

AtCoder TKPPC4-2: I. 互いに素でないペアを持つ N の約数の集合の個数を求めてください。

14547

AtCoder TKPPC4-2: H. 打鍵戦争

14546