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)
2601	Codeforces 613D: Kingdom and its Cities
2600	Codeforces 613C: Necklace
2599	Codeforces 613B: Skills
2598	Codeforces 613A: Peter and Snow Blower
2597	Codeforces 612F: Simba on the Circle
2596	Codeforces 612E: Square Root of Permutation
2595	Codeforces 612D: The Union of k-Segments
2594	Codeforces 612C: Replace To Make Regular Bracket Sequence
2593	Codeforces 612B: HDD is Outdated Technology
2592	Codeforces 612A: The Text Splitting
2591	Codeforces 611H: New Year and Forgotten Tree
2590	Codeforces 611G: New Year and Cake
2589	Codeforces 611F: New Year and Cleaning
2588	Codeforces 611E: New Year and Three Musketeers
2587	Codeforces 611D: New Year and Ancient Prophecy
2586	Codeforces 611C: New Year and Domino
2585	Codeforces 611B: New Year and Old Property
2584	Codeforces 611A: New Year and Days
2583	Codeforces 610E: Alphabet Permutations
2582	Codeforces 610D: Vika and Segments
2581	Codeforces 610C: Harmony Analysis
2580	Codeforces 610B: Vika and Squares
2579	Codeforces 610A: Pasha and Stick
2578	Codeforces 609F: Frogs and mosquitoes
2577	Codeforces 609E: Minimum spanning tree for each edge
2576	Codeforces 609D: Gadgets for dollars and pounds
2575	Codeforces 609C: Load Balancing
2574	Codeforces 609B: The Best Gift
2573	Codeforces 609A: USB Flash Drives
2572	Codeforces 608B: Hamming Distance Sum
2571	Codeforces 608A: Saitama Destroys Hotel
2570	Codeforces 607E: Cross Sum
2569	Codeforces 607D: Power Tree
2568	Codeforces 607C: Marbles
2567	Codeforces 607B: Zuma
2566	Codeforces 607A: Chain Reaction
2565	Codeforces 606B: Testing Robots
2564	Codeforces 606A: Magic Spheres
2563	Codeforces 605E: Intergalaxy Trips
2562	Codeforces 605D: Board Game
2561	Codeforces 605C: Freelancer's Dreams
2560	Codeforces 605B: Lazy Student
2559	Codeforces 605A: Sorting Railway Cars
2558	Codeforces 604B: More Cowbell
2557	Codeforces 604A: Uncowed Forces
2556	Codeforces 603E: Pastoral Oddities
2555	Codeforces 603D: Ruminations on Ruminants
2554	Codeforces 603C: Lieges of Legendre
2553	Codeforces 603B: Moodular Arithmetic
2552	Codeforces 603A: Alternative Thinking

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

2601

Codeforces 613D: Kingdom and its Cities

2600

Codeforces 613C: Necklace

2599

Codeforces 613B: Skills

2598

Codeforces 613A: Peter and Snow Blower

2597

Codeforces 612F: Simba on the Circle

2596