The O(n) Club: Best Time to Buy and Sell Stock III: Survive the Two-Trade Gauntlet
The O(n) Club: Best Time to Buy and Sell Stock III — Survive the Two-Trade Gauntlet ⚡ TL;DR Buy, sell, buy, sell—can you time these two trades…
The O(n) Club: Stock Profit With Cooldown: Because Wall Street Needs Naps Too
The O(n) Club: Stock Profit With Cooldown—Because Wall Street Needs Naps Too ⚡ TL;DR If you want to buy and sell stocks for max profit but…
The O(n) Club: Kth Smallest in a Sorted Matrix: Aka Why Binary Search Beats Brute Force (and Caffeine)
The O(n) Club: Kth Smallest in a Sorted Matrix: Aka Why Binary Search Beats Brute Force (and Caffeine) ⚡ TL;DR You want the kth smallest…
The O(n) Club: 4Sum — When Just One More Loop Feels Like a Crime
The O(n) Club: 4Sum — When Just One More Loop Feels Like a Crime ⚡ TL;DR Find four numbers in your array that make a target sum. Yes, you…
The O(n) Club: Word Search II: Why Your Brute Force Solution Needs an Intervention
The O(n) Club: Word Search II—Why Your Brute Force Solution Needs an Intervention ⚡ TL;DR Want to find every dictionary word in a letter grid,…
The O(n) Club: Trapping Rain Water: Arrays, Puddles, and Other Unexpected Flood Zones
The O(n) Club: Trapping Rain Water—Arrays, Puddles, and Other Unexpected Flood Zones ⚡ TL;DR Given a list of bar heights, your job is to…
The O(n) Club: Find-All-Duplicates—No HashMaps, No Regrets
The O(n) Club: Find-All-Duplicates—No HashMaps, No Regrets ⚡ TL;DR Given an array stuffed with numbers from 1 to n, some appear once, some…
The O(n) Club: Burst Balloons: When DP Pops and Padding Saves Your Sanity
The O(n) Club: Burst Balloons—When DP Pops and Padding Saves Your Sanity ⚡ TL;DR Maximum coins by popping balloons—but if you think popping…
The O(n) Club: Minimum Size Subarray Sum (How to Outsmart Prefix Sums on LeetCode 209)
The O(n) Club: Minimum Size Subarray Sum (How to Outsmart Prefix Sums on LeetCode 209) ⚡ TL;DR Here’s the deal: given an array of…
The O(n) Club: Remove Duplicates from Sorted Array—Why Is This Still an Interview Question?
The O(n) Club: Remove Duplicates from Sorted Array—Why Is This Still an Interview Question? ⚡ TL;DR Your boss (or LeetCode, or that one smug…