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)
17751	DMOJ Google Code Jam '12 Round 1A Problem A - Password Problem
17750	DMOJ Google Code Jam '12 Qualification Round Problem D - Hall of Mirrors
17749	DMOJ Google Code Jam '12 Qualification Round Problem C - Recycled Numbers
17748	DMOJ Google Code Jam '12 Qualification Round Problem B - Dancing With the Googlers
17747	DMOJ Google Code Jam '12 Qualification Round Problem A - Speaking in Tongues
17746	DMOJ Google Code Jam '11 Round 1A Problem C - Pseudominion
17745	DMOJ Google Code Jam '11 Round 1A Problem B - The Killer Word
17744	DMOJ Google Code Jam '11 Round 1A Problem A - FreeCell Statistics
17743	DMOJ Google Code Jam '11 Qualification Round Problem D - GoroSort
17742	DMOJ Google Code Jam '11 Qualification Round Problem C - Magicka
17741	DMOJ Google Code Jam '11 Qualification Round Problem B - Candy Splitting
17740	DMOJ Google Code Jam '11 Qualification Round Problem A - Bot Trust
17739	DMOJ Google Code Jam '10 Round 1A Problem C - Number Game
17738	DMOJ Google Code Jam '10 Round 1A Problem B - Make it Smooth
17737	DMOJ Google Code Jam '10 Round 1A Problem A - Rotate
17736	DMOJ Google Code Jam '10 Qualification Round Problem C - Theme Park
17735	DMOJ Google Code Jam '10 Qualification Round Problem B - Snapper Chain
17734	DMOJ Google Code Jam '10 Qualification Round Problem A - Fair Warning
17733	DMOJ Google Code Jam '09 Round 1A Problem C - Collecting Cards
17732	DMOJ Google Code Jam '09 Round 1A Problem B - Crossing the Road
17731	DMOJ Google Code Jam '09 Round 1A Problem A - Multi-base happiness
17730	DMOJ Google Code Jam '09 Qualification Round Problem C - Welcome to Code Jam
17729	DMOJ Google Code Jam '09 Qualification Round Problem B - Watersheds
17728	DMOJ Google Code Jam '09 Qualification Round Problem A - Alien Language
17727	DMOJ Google Code Jam '08 Round 1A Problem C - Numbers
17726	DMOJ Google Code Jam '08 Round 1A Problem B - Milkshakes
17725	DMOJ Google Code Jam '08 Round 1A Problem A - Minimum Scalar Product
17724	DMOJ Google Code Jam '08 Qualification Round Problem C - Train Timetable
17723	DMOJ Google Code Jam '08 Qualification Round Problem B - Saving the Universe
17722	DMOJ Google Code Jam '08 Qualification Round Problem A - Fly Swatter
17721	DMOJ GCC '16 P3 - Hang Gliding Fun
17720	DMOJ GCC '16 P2 - Classified Documents
17719	DMOJ GCC '16 P1 - Watching Anime
17718	DMOJ The Game of Nim
17717	DMOJ PEG Test '11 - Cyclopian Puzzle
17716	DMOJ PEG Test '11 - Cyclopian Census
17715	DMOJ PEG Test '11 - Cyclopian Cash
17714	DMOJ PEG Test '11 - Cyclopian Suits
17713	DMOJ PEG Test '11 - Cyclopian Air
17712	DMOJ Angie and Functions (Hard)
17711	DMOJ Flip the Switches
17710	DMOJ Imperative French
17709	DMOJ The Fox and the Wolf
17708	DMOJ Foxlings
17707	DMOJ Anti-Fire Fox
17706	DMOJ A Floyd-Warshall Problem
17705	DMOJ Fizz Coke
17704	DMOJ Fixing Shirts
17703	DMOJ Firebending
17702	DMOJ Figurines

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

17751

DMOJ Google Code Jam '12 Round 1A Problem A - Password Problem

17750

DMOJ Google Code Jam '12 Qualification Round Problem D - Hall of Mirrors

17749

DMOJ Google Code Jam '12 Qualification Round Problem C - Recycled Numbers

17748

DMOJ Google Code Jam '12 Qualification Round Problem B - Dancing With the Googlers

17747

DMOJ Google Code Jam '12 Qualification Round Problem A - Speaking in Tongues

17746