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)
17451	DMOJ DWITE '11 R3 #4 - ABCA Maze
17450	DMOJ DWITE '11 R3 #3 - Combo Discounts
17449	DMOJ DWITE '11 R3 #2 - Magical Ponds
17448	DMOJ DWITE '11 R3 #1 - Weighted Presents
17447	DMOJ DWITE '11 R2 #5 - Portals Check
17446	DMOJ DWITE '11 R2 #4 - Bear Trees
17445	DMOJ DWITE '11 R2 #3 - Anonymous Shopping
17444	DMOJ DWITE '11 R2 #2 - Scratch Card
17443	DMOJ DWITE '11 R2 #1 - Wandering Billy
17442	DMOJ DWITE '11 R1 #5 - Tattarrattat
17441	DMOJ DWITE '11 R1 #4 - C001 Numbers
17440	DMOJ DWITE '11 R1 #3 - Take a Walk
17439	DMOJ DWITE '11 R1 #2 - Penny Game
17438	DMOJ DWITE '11 R1 #1 - Arab-lish Numbers
17437	DMOJ DWITE '10 R5 #5 - Cube World
17436	DMOJ DWITE '10 R5 #4 - New type of wordplay
17435	DMOJ DWITE '10 R5 #3 - Balancing Act
17434	DMOJ DWITE '10 R5 #2 - Safe from Rooks
17433	DMOJ DWITE '10 R5 #1 - Colourful Words
17432	DMOJ DWITE '10 R4 #5 - Sleepwalking Probabilities
17431	DMOJ DWITE '10 R4 #4 - Mountain Hiking
17430	DMOJ DWITE '10 R4 #3 - Binary Weight
17429	DMOJ DWITE '10 R4 #2 - Primal Numbers
17428	DMOJ DWITE '10 R4 #1 - Future Printer
17427	DMOJ DWITE '10 R3 #5 - E-Searching
17426	DMOJ DWITE '10 R3 #4 - Forest Fires
17425	DMOJ DWITE '10 R3 #3 - Dominos Tiling
17424	DMOJ DWITE '10 R3 #2 - Unit rectangles
17423	DMOJ DWITE '10 R3 #1 - Integers along a line
17422	DMOJ DWITE '10 R2 #5 - Cogwheels
17421	DMOJ DWITE '10 R2 #4 - Fractions to Decimal
17420	DMOJ DWITE '10 R2 #3 - Escape and Loot
17419	DMOJ DWITE '10 R2 #2 - Seating Arrangement
17418	DMOJ DWITE '10 R2 #1 - Pattern Matching
17417	DMOJ DWITE '10 R1 #5 - Ricochet Robot
17416	DMOJ DWITE '10 R1 #4 - Planting Trees
17415	DMOJ DWITE '10 R1 #3 - Power tiles
17414	DMOJ DWITE '10 R1 #2 - Robot Vacuum Prototype
17413	DMOJ DWITE '10 R1 #1 - Age Gate
17412	DMOJ DWITE '09 R7 #5 - Snapper Chain
17411	DMOJ DWITE '09 R7 #4 - What is this Algebra?
17410	DMOJ DWITE '09 R7 #3 - Oil Spill Area
17409	DMOJ DWITE '09 R7 #2 - Sum of Primes
17408	DMOJ DWITE '09 R7 #1 - Binary Equipment
17407	DMOJ DWITE '09 R6 #5 - Air Travel Planning
17406	DMOJ DWITE '09 R6 #4 - Time for Change
17405	DMOJ DWITE '09 R6 #3 - Bill Amendments
17404	DMOJ DWITE '09 R6 #2 - Round to power of two
17403	DMOJ DWITE '09 R6 #1 - ROT13 Encryption
17402	DMOJ DWITE '09 R5 #5 - Weak Passwords

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

17451

DMOJ DWITE '11 R3 #4 - ABCA Maze

17450

DMOJ DWITE '11 R3 #3 - Combo Discounts

17449

DMOJ DWITE '11 R3 #2 - Magical Ponds

17448

DMOJ DWITE '11 R3 #1 - Weighted Presents

17447

DMOJ DWITE '11 R2 #5 - Portals Check

17446