The O(n) Club

The O(n) Club

Welcome to The O(n) Club – where algorithms run smooth, loops are tight, and Big O isn’t just notation… it’s a lifestyle. This is your elite collection of 500 handpicked LeetCode challenges that matter. From brute force battles to dynamic programming dance-offs, this category is your personal dojo of efficiency, elegance, and edge-case mastery. Expect deep dives, optimal patterns, real-world system design parallels, and code that doesn’t just pass — it flies. If you’re prepping for interviews at FAANG, startups, or just flexing your CS muscles, The O(n) Club is your VIP section.

The O(n) Club

2 Min Read

onFebruary 10, 2025

The O(n) Club: Edge-Walking Your Way Through 2D Matrix Search (No More Row-by-Row Regret)

The O(n) Club: Edge-Walking Your Way Through 2D Matrix Search (No More Row-by-Row Regret) ⚡ TL;DR Don’t let a sorted 2D matrix make you…

The O(n) Club

2 Min Read

onFebruary 9, 2025

The O(n) Club: Longest Common Prefix for Devs Who Love Autocomplete More Than Typing

The O(n) Club: Longest Common Prefix for Devs Who Love Autocomplete More Than Typing ⚡ TL;DR The mission: Find the longest prefix all strings…

The O(n) Club

2 Min Read

onFebruary 9, 2025

The O(n) Club: Stock Profiteering With Pac-Man Instincts

The O(n) Club: Stock Profiteering With Pac-Man Instincts ⚡ TL;DR Every time your stock inches up, cash out the difference. Don’t stare…

The O(n) Club

2 Min Read

onFebruary 8, 2025

The O(n) Club: Linked List Cycle Detection, or Why Tortoises Win at Java

The O(n) Club: Linked List Cycle Detection, or Why Tortoises Win at Java ⚡ TL;DR Is your linked list accidentally hosting the world’s…

The O(n) Club

1 Min Read

onFebruary 8, 2025

The O(n) Club: Maximal Square: When DP Plays Tetris With Your Sanity

The O(n) Club: Maximal Square—When DP Plays Tetris With Your Sanity ⚡ TL;DR Tired of brute-forcing every square in a 2D matrix of…

The O(n) Club

3 Min Read

onFebruary 7, 2025

The O(n) Club: Word Ladder (LeetCode 127): BFS Wizardry Meets Word Jenga

The O(n) Club: Word Ladder (LeetCode 127): BFS Wizardry Meets Word Jenga ⚡ TL;DR Turn beginWord into endWord, one letter per move, using only…

The O(n) Club

1 Min Read

onFebruary 7, 2025

The O(n) Club: Unique Binary Search Trees—Or, Why Catalan Numbers Rule the Forest

The O(n) Club: Unique Binary Search Trees—Or, Why Catalan Numbers Rule the Forest ⚡ TL;DR Want to know how many different BSTs you can make…

The O(n) Club

2 Min Read

onFebruary 6, 2025

The O(n) Club: Partition Equal Subset Sum: Arrays at the Divorce Court

The O(n) Club: Partition Equal Subset Sum—Arrays at the Divorce Court ⚡ TL;DR Can you separate an array of positive integers into two squads…

The O(n) Club

3 Min Read

onFebruary 6, 2025

The O(n) Club: Inorder Traversal: Sorted Drama in Binary Trees — O(n) Club Style

The O(n) Club: Inorder Traversal — Sorted Drama in Binary Trees ⚡ TL;DR Inorder traversal is your “left, root, right” magic trick for binary…

The O(n) Club

1 Min Read

onFebruary 5, 2025

The O(n) Club: Jump Game II — Greedy Hops That’ll Save Your Coding Soul

The O(n) Club: Jump Game II — Greedy Hops That’ll Save Your Coding Soul