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)
5951	Codeforces 1335F: Robots on a Grid
5950	Codeforces 1335E2: Three Blocks Palindrome (hard version)
5949	Codeforces 1335E1: Three Blocks Palindrome (easy version)
5948	Codeforces 1335D: Anti-Sudoku
5947	Codeforces 1335C: Two Teams Composing
5946	Codeforces 1335B: Construct the String
5945	Codeforces 1335A: Candies and Two Sisters
5944	Codeforces 1334G: Substring Search
5943	Codeforces 1334F: Strange Function
5942	Codeforces 1334E: Divisor Paths
5941	Codeforces 1334D: Minimum Euler Cycle
5940	Codeforces 1334C: Circle of Monsters
5939	Codeforces 1334B: Middle Class
5938	Codeforces 1334A: Level Statistics
5937	Codeforces 1333F: Kate and imperfection
5936	Codeforces 1333E: Road to 1600
5935	Codeforces 1333D: Challenges in school №41
5934	Codeforces 1333C: Eugene and an array
5933	Codeforces 1333B: Kind Anton
5932	Codeforces 1333A: Little Artem
5931	Codeforces 1332G: No Monotone Triples
5930	Codeforces 1332F: Independent Set
5929	Codeforces 1332E: Height All the Same
5928	Codeforces 1332D: Walk on Matrix
5927	Codeforces 1332C: K-Complete Word
5926	Codeforces 1332B: Composite Coloring
5925	Codeforces 1332A: Exercising Walk
5924	Codeforces 1331H: It's showtime
5923	Codeforces 1331G: Lingua Romana
5922	Codeforces 1331F: Elementary!
5921	Codeforces 1331E: Jordan Smiley
5920	Codeforces 1331D: Again?
5919	Codeforces 1331C: ...And after happily lived ever they
5918	Codeforces 1331B: Limericks
5917	Codeforces 1331A: Is it rated?
5916	Codeforces 1330B: Dreamoon Likes Permutations
5915	Codeforces 1330A: Dreamoon and Ranking Collection
5914	Codeforces 1329E: Dreamoon Loves AA
5913	Codeforces 1329D: Dreamoon Likes Strings
5912	Codeforces 1329C: Drazil Likes Heap
5911	Codeforces 1329B: Dreamoon Likes Sequences
5910	Codeforces 1329A: Dreamoon Likes Coloring
5909	Codeforces 1328F: Make k Equal
5908	Codeforces 1328E: Tree Queries
5907	Codeforces 1328D: Carousel
5906	Codeforces 1328C: Ternary XOR
5905	Codeforces 1328B: K-th Beautiful String
5904	Codeforces 1328A: Divisibility Problem
5903	Codeforces 1327G: Letters and Question Marks
5902	Codeforces 1327F: AND Segments

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

5951

Codeforces 1335F: Robots on a Grid

5950

Codeforces 1335E2: Three Blocks Palindrome (hard version)

5949

Codeforces 1335E1: Three Blocks Palindrome (easy version)

5948

Codeforces 1335D: Anti-Sudoku

5947

Codeforces 1335C: Two Teams Composing

5946