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)
10101	AtCoder ABC249: E. RLE
10100	AtCoder ABC249: D. Index Trio
10099	AtCoder ABC249: C. Just K
10098	AtCoder ABC249: B. Perfect String
10097	AtCoder ABC249: A. Jogging
10096	AtCoder ABC248: Ex. Beautiful Subsequences
10095	AtCoder ABC248: G. GCD cost on the tree
10094	AtCoder ABC248: F. Keep Connect
10093	AtCoder ABC248: E. K-colinear Line
10092	AtCoder ABC248: D. Range Count Query
10091	AtCoder ABC248: C. Dice Sum
10090	AtCoder ABC248: B. Slimes
10089	AtCoder ABC248: A. Lacked Number
10088	AtCoder ABC247: Ex. Rearranging Problem
10087	AtCoder ABC247: G. Dream Team
10086	AtCoder ABC247: F. Cards
10085	AtCoder ABC247: E. Max Min
10084	AtCoder ABC247: D. Cylinder
10083	AtCoder ABC247: C. 1 2 1 3 1 2 1
10082	AtCoder ABC247: B. Unique Nicknames
10081	AtCoder ABC247: A. Move Right
10080	AtCoder ABC246: Ex. 01? Queries
10079	AtCoder ABC246: G. Game on Tree 3
10078	AtCoder ABC246: F. typewriter
10077	AtCoder ABC246: E. Bishop 2
10076	AtCoder ABC246: D. 2-variable Function
10075	AtCoder ABC246: C. Coupon
10074	AtCoder ABC246: B. Get Closer
10073	AtCoder ABC246: A. Four Points
10072	AtCoder ABC245: Ex. Product Modulo 2
10071	AtCoder ABC245: G. Foreign Friends
10070	AtCoder ABC245: F. Endless Walk
10069	AtCoder ABC245: E. Wrapping Chocolate
10068	AtCoder ABC245: D. Polynomial division
10067	AtCoder ABC245: C. Choose Elements
10066	AtCoder ABC245: B. Mex
10065	AtCoder ABC245: A. Good morning
10064	AtCoder ABC244: Ex. Linear Maximization
10063	AtCoder ABC244: G. Construct Good Path
10062	AtCoder ABC244: F. Shortest Good Path
10061	AtCoder ABC244: E. King Bombee
10060	AtCoder ABC244: D. Swap Hats
10059	AtCoder ABC244: C. Yamanote Line Game
10058	AtCoder ABC244: B. Go Straight and Turn Right
10057	AtCoder ABC244: A. Last Letter
10056	AtCoder ABC243: Ex. Builder Takahashi (Enhanced version)
10055	AtCoder ABC243: G. Sqrt
10054	AtCoder ABC243: F. Lottery
10053	AtCoder ABC243: E. Edge Deletion
10052	AtCoder ABC243: D. Moves on Binary Tree

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

10101

AtCoder ABC249: E. RLE

10100

AtCoder ABC249: D. Index Trio

10099

AtCoder ABC249: C. Just K

10098

AtCoder ABC249: B. Perfect String

10097

AtCoder ABC249: A. Jogging

10096