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)
18801	DMOJ OCC '19 B4 - Bussing
18800	DMOJ OCC '19 B3 - Difference
18799	DMOJ OCC '19 B2 - Cinematic
18798	DMOJ OCC '19 B1 - Darcy_Liu
18797	DMOJ ICPC NWERC 2015 E - Elementary Math
18796	DMOJ ICPC NWERC 2015 A - Assigning Workstations
18795	DMOJ ICPC NWERC 2014 F - Finding Lines
18794	DMOJ ICPC NWERC 2011 F - Pool Construction
18793	DMOJ ICPC NWERC 2011 C - Movie Collection
18792	DMOJ ICPC NWERC 2011 A - Binomial Coefficients
18791	DMOJ ICPC NWERC 2005 A - Unequalled Consumption
18790	DMOJ Not an Aho-Corasick Problem
18789	DMOJ Non-space-separated
18788	DMOJ NOI Winter Camp '17 P2: Challenge
18787	DMOJ NOI Winter Camp '09 P1 - A Shortest Path Problem
18786	DMOJ NOIP '99 P4 - Stamp Face Value Design
18785	DMOJ NOIP '99 P3 - Traveller's Budget
18784	DMOJ NOIP '99 P2 - Palindrome Numbers
18783	DMOJ NOIP '99 P1 - Missile Interception
18782	DMOJ NOIP '99 Junior P1 - Cantor Table
18781	DMOJ NOIP '21 P4 - Chess
18780	DMOJ NOIP '21 P3 - Variance
18779	DMOJ NOIP '21 P2 - Sequence
18778	DMOJ NOIP '21 P1 - Saying Numbers
18777	DMOJ NOIP '20 P4 - WeRun
18776	DMOJ NOIP '20 P3 - Game of Moving Ball
18775	DMOJ NOIP '20 P2 - String Matching
18774	DMOJ NOIP '20 P1 - Drainage System
18773	DMOJ NOIP '18 P6 - Defending the Kingdom
18772	DMOJ NOIP '18 P5 - Grid-filling Game
18771	DMOJ NOIP '18 P4 - Travel
18770	DMOJ NOIP '18 P3 - Constructing Tracks
18769	DMOJ NOIP '18 P2 - Currency System
18768	DMOJ NOIP '18 P1 - Paving Roads
18767	DMOJ NOIP '18 Junior P3 - Shuttle Bus
18766	DMOJ NOIP '18 Junior P2 - The Big Battle
18765	DMOJ NOIP '18 Junior P1 - Title Statistics
18764	DMOJ NOIP '15 P5 - Substring
18763	DMOJ NOIP '04 P4 - Bugs Eating Computation
18762	DMOJ NOIP '04 P3 - Chorus Formation
18761	DMOJ NOIP '04 P2 - Combine Fruit
18760	DMOJ NOI '22 Multi-Provincial Team Selection P6 - MIS
18759	DMOJ NOI '22 Multi-Provincial Team Selection P5 - Bracket
18758	DMOJ NOI '22 Multi-Provincial Team Selection P4 - Card
18757	DMOJ NOI '22 Multi-Provincial Team Selection P3 - Community
18756	DMOJ NOI '22 Multi-Provincial Team Selection P2 - Tree
18755	DMOJ NOI '22 Multi-Provincial Team Selection P1 - Preprocessor
18754	DMOJ NOI '99 P6 - Memory Allocation
18753	DMOJ NOI '99 P5 - Optimally Connected Subset
18752	DMOJ NOI '99 P4 - Chessboard Division

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

18801

DMOJ OCC '19 B4 - Bussing

18800

DMOJ OCC '19 B3 - Difference

18799

DMOJ OCC '19 B2 - Cinematic

18798

DMOJ OCC '19 B1 - Darcy_Liu

18797

DMOJ ICPC NWERC 2015 E - Elementary Math

18796