The O(n) Club: Reverse Words in a String III — Don’t Flip Out
The O(n) Club: Reverse Words in a String III — Don’t Flip Out ⚡ TL;DR Don’t go full Exorcist—just reverse each word in the sentence, not the…
The O(n) Club: Count Binary Substrings — Or, Why Brute Force Devs Cry
The O(n) Club: Count Binary Substrings — Or, Why Brute Force Devs Cry ⚡ TL;DR Count every spot where a run of ‘0’s is immediately…
The O(n) Club: Reverse Words in a String – Where Your Spaces Go to Sabotage You
The O(n) Club: Reverse Words in a String – Where Your Spaces Go to Sabotage You ⚡ TL;DR Given a messy string like ” Hello World from…
The O(n) Club: Valid Palindrome: Why Your String Doesn’t Care About Punctuation
The O(n) Club: Valid Palindrome – Why Your String Doesn’t Care About Punctuation ⚡ TL;DR Check if a string’s a palindrome, but ignore…
The O(n) Club: Implement strStr and Dodge That Haystack Hangover
The O(n) Club: Implement strStr and Dodge That Haystack Hangover ⚡ TL;DR You want to find the first spot where ‘needle’ appears in…
The O(n) Club: Backspace String Compare, or: Why Your Undo Key Hates You
The O(n) Club: Backspace String Compare, or: Why Your Undo Key Hates You ⚡ TL;DR You have two strings, both infected with more ‘#’…
The O(n) Club: Is Subsequence: Why Order Matters (and Coffee Helps)
The O(n) Club: Is Subsequence — Why Order Matters (and Coffee Helps) ⚡ TL;DR Checking if s is a subsequence of t? Don’t waste your time (or…
The O(n) Club: Reverse String (LeetCode 344) for the Two-Pointer Skeptics
The O(n) Club: Reverse String (LeetCode 344) for the Two-Pointer Skeptics ⚡ TL;DR Reverse a char array? Grab a pointer for each end, swap…
The O(n) Club: Valid Palindrome II: Palindrome With Training Wheels
The O(n) Club: Valid Palindrome II – Palindrome With Training Wheels ⚡ TL;DR Basically, you get one free pass. Given a string, can it be a…
The O(n) Club: Median from Data Stream—How Heaps Became Your Streaming BFF
The O(n) Club: Median from Data Stream—How Heaps Became Your Streaming BFF ⚡ TL;DR Still sorting your whole list every time for the median,…