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)
13651	AtCoder NIKKEI2019-2-FINAL: C. Largest N
13650	AtCoder NIKKEI2019-2-FINAL: B. NIKKEI String
13649	AtCoder NIKKEI2019-2-FINAL: A. Count Triplets
13648	AtCoder NEWJUDGE-2308-HEURISTIC: A. AtCoder Contest Scheduling (Online Version)
13647	AtCoder NADAFES2022_DAY2: P. Turn it Over
13646	AtCoder NADAFES2022_DAY2: O. Simple Inversion Problem
13645	AtCoder NADAFES2022_DAY2: N. All Crosses
13644	AtCoder NADAFES2022_DAY2: M. Swapping Brackets
13643	AtCoder NADAFES2022_DAY2: L. Min Diff Min
13642	AtCoder NADAFES2022_DAY2: K. Exhibition 3
13641	AtCoder NADAFES2022_DAY2: J. Sum Equality
13640	AtCoder NADAFES2022_DAY2: I. Product of LCM of GCD
13639	AtCoder NADAFES2022_DAY2: H. Tourist on Graph
13638	AtCoder NADAFES2022_DAY2: G. Interval GCD
13637	AtCoder NADAFES2022_DAY2: F. Charge
13636	AtCoder NADAFES2022_DAY2: E. Hamiltonian Circuit
13635	AtCoder NADAFES2022_DAY2: D. NPCA Network
13634	AtCoder NADAFES2022_DAY2: C. Time Bombs
13633	AtCoder NADAFES2022_DAY2: B. Min Max Min
13632	AtCoder NADAFES2022_DAY2: A. ACPN
13631	AtCoder NADAFES2022_DAY1: P. Sum of Max of Difference
13630	AtCoder NADAFES2022_DAY1: O. Swapping Desks
13629	AtCoder NADAFES2022_DAY1: N. Range Flip
13628	AtCoder NADAFES2022_DAY1: M. Random Drawing
13627	AtCoder NADAFES2022_DAY1: L. Lexicographic Euler Tour
13626	AtCoder NADAFES2022_DAY1: K. Li
13625	AtCoder NADAFES2022_DAY1: J. Excluded LCM
13624	AtCoder NADAFES2022_DAY1: I. NPCA Kingdom
13623	AtCoder NADAFES2022_DAY1: H. Traveling PCT Problem
13622	AtCoder NADAFES2022_DAY1: G. Road Closed
13621	AtCoder NADAFES2022_DAY1: F. Mth Next Permutation
13620	AtCoder NADAFES2022_DAY1: E. Even Degree
13619	AtCoder NADAFES2022_DAY1: D. Double Permutations
13618	AtCoder NADAFES2022_DAY1: C. Flood
13617	AtCoder NADAFES2022_DAY1: B. Exist Multiples
13616	AtCoder NADAFES2022_DAY1: A. Max Inversion
13615	AtCoder MUJIN-PC-2018: H. タイル張り
13614	AtCoder MUJIN-PC-2018: G. 移動
13613	AtCoder MUJIN-PC-2018: F. チーム分け
13612	AtCoder MUJIN-PC-2018: E. 迷路
13611	AtCoder MUJIN-PC-2018: D. うほょじご
13610	AtCoder MUJIN-PC-2018: C. 右折
13609	AtCoder MUJIN-PC-2018: B. セキュリティ
13608	AtCoder MUJIN-PC-2018: A. コンテスト名
13607	AtCoder MUJIN-PC-2017: D. Oriented Tree
13606	AtCoder MUJIN-PC-2017: C. Robot and String
13605	AtCoder MUJIN-PC-2017: B. Row to Column
13604	AtCoder MUJIN-PC-2017: A. Robot Racing
13603	AtCoder MUJIN-PC-2016: E. Hexagon
13602	AtCoder MUJIN-PC-2016: D. Parenthesis Sequence

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

13651

AtCoder NIKKEI2019-2-FINAL: C. Largest N

13650

AtCoder NIKKEI2019-2-FINAL: B. NIKKEI String

13649

AtCoder NIKKEI2019-2-FINAL: A. Count Triplets

13648

AtCoder NEWJUDGE-2308-HEURISTIC: A. AtCoder Contest Scheduling (Online Version)

13647

AtCoder NADAFES2022_DAY2: P. Turn it Over

13646