The O(n) Club: Minimum Add to Make Parentheses Valid (And Why Your Editor Hates You)
The O(n) Club: Minimum Add to Make Parentheses Valid (And Why Your Editor Hates You) ⚡ TL;DR Given a string made entirely of ‘(‘…
The O(n) Club: Turning Your String Into a Narcissist—Shortest Palindrome Edition
The O(n) Club: Turning Your String Into a Narcissist—Shortest Palindrome Edition ⚡ TL;DR You want to turn your string s into the shortest…
The O(n) Club: Remove All Adjacent Duplicates in String II—Stack Attack Edition
The O(n) Club: Remove All Adjacent Duplicates in String II—Stack Attack Edition ⚡ TL;DR Input: string + integer k. Goal: keep destroying any…
The O(n) Club: Restore IP Addresses—Dotting Your Way to Sanity
The O(n) Club: Restore IP Addresses—Dotting Your Way to Sanity ⚡ TL;DR Stuff three dots into a digit string until you get every possible valid…
The O(n) Club: Delete Operation for Two Strings — Deleting Your Way to Happiness
The O(n) Club: Delete Operation for Two Strings — Deleting Your Way to Happiness ⚡ TL;DR Want two strings to be identical? Just delete…
The O(n) Club: Serialize and Deserialize BST—Now With 50% Less Useless Data
The O(n) Club: Serialize and Deserialize BST—Now With 50% Less Useless Data ⚡ TL;DR Want to flatten a Binary Search Tree for storage or…
The O(n) Club: Remove All Adjacent Duplicates in String — Now With 100% Less Regret Than Brute Force
The O(n) Club: Remove All Adjacent Duplicates in String — Now With 100% Less Regret Than Brute Force ⚡ TL;DR Stuck deleting every pair of…
The O(n) Club: Letter Case Permutation — Brute Force Meets Java’s Fashion Police
The O(n) Club: Letter Case Permutation — Brute Force Meets Java’s Fashion Police ⚡ TL;DR You get a string. For every letter, you swap its case…
The O(n) Club: Score of Parentheses—Where Mildly Annoying Brackets Become Mathematical Fireworks
The O(n) Club: Score of Parentheses—Where Mildly Annoying Brackets Become Mathematical Fireworks ⚡ TL;DR Don’t (re)curse yourself! You…
The O(n) Club: Palindrome Partitioning II—Fewer Cuts, Less Regret
The O(n) Club: Palindrome Partitioning II—Fewer Cuts, Less Regret ⚡ TL;DR Chop a string into palindromic slices using as few cuts as possible…