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)
15951	DMOJ CCO '99 P2 - Common Words
15950	DMOJ CCO '99 P1 - You Can't Get There From Here
15949	DMOJ CCO '98 P6 - Derek's Dilemma
15948	DMOJ CCO '98 P5 - Text Segmentation
15947	DMOJ CCO '98 P4 - Scoring Curling
15946	DMOJ CCO '98 P3 - Bus Schedule
15945	DMOJ CCO '98 P2 - Message Deciphering
15944	DMOJ CCO '98 P1 - Fibonacci Numbers
15943	DMOJ CCO '97 P6 - Aligning DNA
15942	DMOJ CCO '97 P5 - Space Aliens
15941	DMOJ CCO '97 P4 - High Tide
15940	DMOJ CCO '97 P3 - Porous Stone
15939	DMOJ CCO '97 P2 - Alien Invasion
15938	DMOJ CCO '97 P1 - Palindromes
15937	DMOJ CCO '96 P6 - Hoppers
15936	DMOJ CCO '96 P5 - All Roads Lead Where?
15935	DMOJ CCO '96 P4 - Where's Waldorf?
15934	DMOJ CCO '96 P3 - Quadtrees
15933	DMOJ CCO '96 P2 - SafeBreaker
15932	DMOJ CCO '96 P1 - Train Swapping
15931	DMOJ CCO '23 P6 - Triangle Collection
15930	DMOJ CCO '23 P5 - Travelling Trader
15929	DMOJ CCO '23 P4 - Flip it and Stick it
15928	DMOJ CCO '23 P3 - Line Town
15927	DMOJ CCO '23 P2 - Real Mountains
15926	DMOJ CCO '23 P1 - Binaria
15925	DMOJ CCO '22 P6 - Good Game
15924	DMOJ CCO '22 P5 - Phone Plans
15923	DMOJ CCO '22 P4 - Bi-ing Lottery Treekets
15922	DMOJ CCO '22 P3 - Double Attendance
15921	DMOJ CCO '22 P2 - Rainy Markets
15920	DMOJ CCO '22 P1 - Alternating Heights
15919	DMOJ CCO '21 P6 - Loop Town
15918	DMOJ CCO '21 P5 - Bread First Search
15917	DMOJ CCO '21 P4 - Travelling Merchant
15916	DMOJ CCO '21 P3 - Through Another Maze Darkly
15915	DMOJ CCO '21 P2 - Weird Numeral System
15914	DMOJ CCO '21 P1 - Swap Swap Sort
15913	DMOJ CCO '20 P6 - Shopping Plans
15912	DMOJ CCO '20 P5 - Interval Collection
15911	DMOJ CCO '20 P4 - Travelling Salesperson
15910	DMOJ CCO '20 P3 - Mountains and Valleys
15909	DMOJ CCO '20 P2 - Exercise Deadlines
15908	DMOJ CCO '20 P1 - A Game with Grundy
15907	DMOJ CCO '19 P6 - Bad Codes
15906	DMOJ CCO '19 P5 - Marshmallow Molecules
15905	DMOJ CCO '19 P4 - Card Scoring
15904	DMOJ CCO '19 P3 - Winter Driving
15903	DMOJ CCO '19 P2 - Sirtet
15902	DMOJ CCO '19 P1 - Human Error

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

15951

DMOJ CCO '99 P2 - Common Words

15950

DMOJ CCO '99 P1 - You Can't Get There From Here

15949

DMOJ CCO '98 P6 - Derek's Dilemma

15948

DMOJ CCO '98 P5 - Text Segmentation

15947

DMOJ CCO '98 P4 - Scoring Curling

15946