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)
4501	Codeforces 1044C: Optimal Polygon Perimeter
4500	Codeforces 1044B: Intersecting Subtrees
4499	Codeforces 1044A: The Tower is Going Home
4498	Codeforces 1043G: Speckled Band
4497	Codeforces 1043F: Make It One
4496	Codeforces 1043E: Train Hard, Win Easy
4495	Codeforces 1043D: Mysterious Crime
4494	Codeforces 1043C: Smallest Word
4493	Codeforces 1043B: Lost Array
4492	Codeforces 1043A: Elections
4491	Codeforces 1042F: Leaf Sets
4490	Codeforces 1042E: Vasya and Magic Matrix
4489	Codeforces 1042D: Petya and Array
4488	Codeforces 1042C: Array Product
4487	Codeforces 1042B: Vitamins
4486	Codeforces 1042A: Benches
4485	Codeforces 1041F: Ray in the tube
4484	Codeforces 1041E: Tree Reconstruction
4483	Codeforces 1041D: Glider
4482	Codeforces 1041C: Coffee Break
4481	Codeforces 1041B: Buying a TV Set
4480	Codeforces 1041A: Heist
4479	Codeforces 1040B: Shashlik Cooking
4478	Codeforces 1040A: Palindrome Dance
4477	Codeforces 1039E: Summer Oenothera Exhibition
4476	Codeforces 1039D: You Are Given a Tree
4475	Codeforces 1039C: Network Safety
4474	Codeforces 1039B: Subway Pursuit
4473	Codeforces 1039A: Timetable
4472	Codeforces 1038F: Wrap Around
4471	Codeforces 1038E: Maximum Matching
4470	Codeforces 1038D: Slime
4469	Codeforces 1038C: Gambling
4468	Codeforces 1038B: Non-Coprime Partition
4467	Codeforces 1038A: Equality
4466	Codeforces 1037H: Security
4465	Codeforces 1037G: A Game on Strings
4464	Codeforces 1037F: Maximum Reduction
4463	Codeforces 1037E: Trips
4462	Codeforces 1037D: Valid BFS?
4461	Codeforces 1037C: Equalize
4460	Codeforces 1037B: Reach Median
4459	Codeforces 1037A: Packets
4458	Codeforces 1036G: Sources and Sinks
4457	Codeforces 1036F: Relatively Prime Powers
4456	Codeforces 1036E: Covered Points
4455	Codeforces 1036D: Vasya and Arrays
4454	Codeforces 1036C: Classy Numbers
4453	Codeforces 1036B: Diagonal Walking v.2
4452	Codeforces 1036A: Function Height

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

4501

Codeforces 1044C: Optimal Polygon Perimeter

4500

Codeforces 1044B: Intersecting Subtrees

4499

Codeforces 1044A: The Tower is Going Home

4498

Codeforces 1043G: Speckled Band

4497

Codeforces 1043F: Make It One

4496