The O(n) Club: Unique Subsets With Twins (How to Uninvite Duplicate Guests)
The O(n) Club: Unique Subsets With Twins (How to Uninvite Duplicate Guests) ⚡ TL;DR Need to find every combo of numbers in an array (even if…
The Mutex Club: The Readers-Writers Conundrum Driving Developers Insane
The Mutex Club: The Readers-Writers Conundrum Driving Developers Insane Ever tried juggling ten SELECTs and a lone UPDATE without watching…
The Mutex Club: Producer-Consumer with BlockingQueue (No Lock Drama)
Key Insights # BlockingQueue as your thread bouncer Java’s BlockingQueue (java.util.concurrent) is the no-drama handoff between producers and…
The O(n) Club: Wildcard Matching: How to Outsmart Your Inner Greedy Asterisk
The O(n) Club: Wildcard Matching—How to Outsmart Your Inner Greedy Asterisk ⚡ TL;DR This isn’t regex, it’s chaos—Wildcard Matching…
The O(n) Club: Insert Interval: The Algorithmic Family Reunion You’ll Never Escape
The O(n) Club: Insert Interval — The Algorithmic Family Reunion You’ll Never Escape ⚡ TL;DR You’re handed a bunch of…
The Mutex Club: Mastering Thread-Safe Logging in Microservices
Key Insights # Thread-safe logging prevents a log soup When microservices spin up dozens of threads, logging without locks is like letting ten…
The Mutex Club: Semaphore vs. Rate Limiter – Who Gets to Play Traffic Cop?
Semaphores, Rate Limiting, and Why Your API Isn’t a Free-For-All Ever tried hitting a public API during peak hours, only to watch your…
The O(n) Club: Linked List to BST—the Only Speed Limit is Your Pointer
The O(n) Club: Linked List to BST—the Only Speed Limit is Your Pointer ⚡ TL;DR Turning a sorted singly-linked list into a balanced BST? Sure,…
The O(n) Club: Path Sum II: The Quest for Leafy Sums (or, Why Your Paths Keep Mutating)
The O(n) Club: Path Sum II – The Quest for Leafy Sums (or, Why Your Paths Keep Mutating) ⚡ TL;DR Given a binary tree and a target sum, find…
The Mutex Club: Taming Batch Jobs with Java’s ExecutorService
Key Insights # Batch Submission Patterns Use submit() in a loop or the one-liner invokeAll() to fire off a pile of Callable or Runnable tasks.…