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…
The O(n) Club: Distinct Subsequences, or How to Skip Letters Like a Pro (and Keep Your Sanity)
The O(n) Club: Distinct Subsequences, or How to Skip Letters Like a Pro (and Keep Your Sanity) ⚡ TL;DR Want the number of ways to get t as a…
The O(n) Club: Valid Parenthesis String — Greedy for Sanity, Wild About Wildcards
The O(n) Club: Valid Parenthesis String — Greedy for Sanity, Wild About Wildcards ⚡ TL;DR This interview classic wants you to check if a…
The O(n) Club: Repeated Substring Pattern—Now With 100% More Magic Rope
The O(n) Club: Repeated Substring Pattern—Now With 100% More Magic Rope ⚡ TL;DR Want to know if your string is secretly “la la la”…
The O(n) Club: Zigzag Conversion – How to Break, Not Break, And Break Your Strings
The O(n) Club: Zigzag Conversion – How to Break, Not Break, And Break Your Strings ⚡ TL;DR Take your input string, sprinkle it…
The O(n) Club: Minimum Remove to Make Valid Parentheses — Java’s Answer to Your Bracket Nightmares
The O(n) Club: Minimum Remove to Make Valid Parentheses — Java’s Answer to Your Bracket Nightmares ⚡ TL;DR Dev nightmare: You have a string…