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)
12801	AtCoder JOI2008HO: A. 碁石ならべ
12800	AtCoder JOI2007YO: F. 通学経路
12799	AtCoder JOI2007YO: E. 品質検査
12798	AtCoder JOI2007YO: D. カードの並び替え
12797	AtCoder JOI2007YO: C. シーザー暗号
12796	AtCoder JOI2007YO: B. 未提出者は誰だ
12795	AtCoder JOI2007YO: A. 得点
12794	AtCoder JOI2007HO: E. 最軽量のモビール
12793	AtCoder JOI2007HO: D. 最悪の記者
12792	AtCoder JOI2007HO: C. 最古の遺跡
12791	AtCoder JOI2007HO: B. 最長の階段
12790	AtCoder JOI2007HO: A. 最大の和
12789	AtCoder JOI2006YO: E. JOI 2006 予選問題5
12788	AtCoder JOI2006YO: D. JOI 2006 予選問題4
12787	AtCoder JOI2006YO: C. JOI 2006 予選問題3
12786	AtCoder JOI2006YO: B. JOI 2006 予選問題2
12785	AtCoder JOI2006YO: A. JOI 2006 予選問題1
12784	AtCoder JOI2006HO: E. JOI 2006 本選問題5
12783	AtCoder JOI2006HO: D. JOI 2006 本選問題4
12782	AtCoder JOI2006HO: C. JOI 2006 本選問題3
12781	AtCoder JOI2006HO: B. JOI 2006 本選問題2
12780	AtCoder JOI2006HO: A. JOI 2006 本選問題1
12779	AtCoder JAG2018SUMMER-DAY2: K. Short LIS
12778	AtCoder JAG2018SUMMER-DAY2: J. AB Sort
12777	AtCoder JAG2018SUMMER-DAY2: I. ADD DIV MAX RESTORE
12776	AtCoder JAG2018SUMMER-DAY2: H. Prefix Suffix Free
12775	AtCoder JAG2018SUMMER-DAY2: G. Construct One Point
12774	AtCoder JAG2018SUMMER-DAY2: F. Point Sequences
12773	AtCoder JAG2018SUMMER-DAY2: E. Self-contained
12772	AtCoder JAG2018SUMMER-DAY2: D. Knapsack And Queries
12771	AtCoder JAG2018SUMMER-DAY2: C. Equiangular
12770	AtCoder JAG2018SUMMER-DAY2: B. Coins
12769	AtCoder JAG2018SUMMER-DAY2: A. 10^N+7
12768	AtCoder JAG2017SUMMER-DAY3: K. Permutation Period
12767	AtCoder JAG2017SUMMER-DAY3: J. Sum Source Detection
12766	AtCoder JAG2017SUMMER-DAY3: I. Librarian's Work
12765	AtCoder JAG2017SUMMER-DAY3: H. Tiny Room
12764	AtCoder JAG2017SUMMER-DAY3: G. Low Range-Sum Matrix
12763	AtCoder JAG2017SUMMER-DAY3: F. Endless BFS
12762	AtCoder JAG2017SUMMER-DAY3: E. Route Calculator
12761	AtCoder JAG2017SUMMER-DAY3: D. Janken Master
12760	AtCoder JAG2017SUMMER-DAY3: C. Ninja Map
12759	AtCoder JAG2017SUMMER-DAY3: B. Slimming Plan
12758	AtCoder JAG2017SUMMER-DAY3: A. Star in Parentheses
12757	AtCoder JAG2017SUMMER-DAY1: K. パンプキン
12756	AtCoder JAG2017SUMMER-DAY1: J. クッパ
12755	AtCoder JAG2017SUMMER-DAY1: I. ルーク
12754	AtCoder JAG2017SUMMER-DAY1: H. イベルタル
12753	AtCoder JAG2017SUMMER-DAY1: G. ツーリスト問題
12752	AtCoder JAG2017SUMMER-DAY1: F. 極小部分列

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

12801

AtCoder JOI2008HO: A. 碁石ならべ

12800

AtCoder JOI2007YO: F. 通学経路

12799

AtCoder JOI2007YO: E. 品質検査

12798

AtCoder JOI2007YO: D. カードの並び替え

12797

AtCoder JOI2007YO: C. シーザー暗号

12796