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)
4001	Codeforces 932E: Team Work
4000	Codeforces 932D: Tree
3999	Codeforces 932C: Permutation Cycle
3998	Codeforces 932B: Recursive Queries
3997	Codeforces 932A: Palindromic Supersequence
3996	Codeforces 931C: Laboratory Work
3995	Codeforces 931B: World Cup
3994	Codeforces 931A: Friends Meeting
3993	Codeforces 930E: Coins Exhibition
3992	Codeforces 930D: Game with Tokens
3991	Codeforces 930C: Teodor is not a liar!
3990	Codeforces 930B: Game with String
3989	Codeforces 930A: Peculiar apple-tree
3988	Codeforces 929D: Пограничные врата
3987	Codeforces 929C: Красивая команда
3986	Codeforces 929B: Места в самолёте
3985	Codeforces 929A: Прокат велосипедов
3984	Codeforces 928D: Autocompletion
3983	Codeforces 928C: Dependency management
3982	Codeforces 928B: Chat
3981	Codeforces 928A: Login Verification
3980	Codeforces 927A: BuberPool Taxi Optimization
3979	Codeforces 926J: Segments
3978	Codeforces 926I: A Vital Problem
3977	Codeforces 926H: Endless Roses Most Beautiful
3976	Codeforces 926G: Large Bouquets
3975	Codeforces 926F: Mobile Communications
3974	Codeforces 926E: Merge Equal Elements
3973	Codeforces 926D: Choose Place
3972	Codeforces 926C: Is This a Zebra?
3971	Codeforces 926B: Add Points
3970	Codeforces 926A: 2-3-numbers
3969	Codeforces 925F: Parametric Circulation
3968	Codeforces 925E: May Holidays
3967	Codeforces 925D: Aztec Catacombs
3966	Codeforces 925C: Big Secret
3965	Codeforces 925B: Resource Distribution
3964	Codeforces 925A: Stairs and Elevators
3963	Codeforces 924F: Minimal Subset Difference
3962	Codeforces 924E: Wardrobe
3961	Codeforces 924D: Contact ATC
3960	Codeforces 924C: Riverside Curio
3959	Codeforces 924B: Three-level Laser
3958	Codeforces 924A: Mystical Mosaic
3957	Codeforces 923F: Public Service
3956	Codeforces 923E: Perpetual Subtraction
3955	Codeforces 923D: Picking Strings
3954	Codeforces 923C: Perfect Security
3953	Codeforces 923B: Producing Snow
3952	Codeforces 923A: Primal Sport

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

4001

Codeforces 932E: Team Work

4000

Codeforces 932D: Tree

3999

Codeforces 932C: Permutation Cycle

3998

Codeforces 932B: Recursive Queries

3997

Codeforces 932A: Palindromic Supersequence

3996