The O(n) Club: Path Sum and the Java Leaf-Hunting Gauntlet
The O(n) Club: Path Sum and the Java Leaf-Hunting Gauntlet ⚡ TL;DR Loyal binary searchers, here’s the deal: You want to know if any…
The O(n) Club: Binary Search Tree Iterator: Lazy Traversal for Stack-Savvy Devs
The O(n) Club: Binary Search Tree Iterator: Lazy Traversal for Stack-Savvy Devs ⚡ TL;DR You need to traverse a BST in-order, get the next…
The O(n) Club: Longest Increasing Path in a Matrix — Because Who Needs Diagonals?
The O(n) Club: Longest Increasing Path in a Matrix — Because Who Needs Diagonals? ⚡ TL;DR Find the longest path in a matrix by moving up,…
The O(n) Club: Shortest Unsorted Subarray — Only Sort What’s Broken
The O(n) Club: Shortest Unsorted Subarray — Only Sort What’s Broken ⚡ TL;DR Given an array of integers, find the length of the shortest…
The O(n) Club: Lowest Common Ancestor in a BST — The Ancestor Hunt Nobody Asked For
The O(n) Club: Lowest Common Ancestor in a BST — The Ancestor Hunt Nobody Asked For ⚡ TL;DR Want to find the nearest shared ancestor in a BST?…
The O(n) Club: Minimum Height Trees, or How to Avoid Roast CPU
The O(n) Club: Minimum Height Trees, or How to Avoid Roast CPU ⚡ TL;DR If you’re about to brute-force every possible root in a tree to…
The O(n) Club: Same Tree: If You Flattened It, You Broke It
The O(n) Club: Same Tree — If You Flattened It, You Broke It ⚡ TL;DR Stop trying to flatten, traverse, or philosophize about your trees. If…
The O(n) Club: K Closest Points to Origin: Or, How to Avoid a Heap of Regret
The O(n) Club: K Closest Points to Origin—Or, How to Avoid a Heap of Regret ⚡ TL;DR Don’t overthink it: Want the k closest 2D points to (0,…
The O(n) Club: Odd Even Linked List: When Indices, Not Values, Go Rogue
The O(n) Club: Odd Even Linked List — When Indices, Not Values, Go Rogue ⚡ TL;DR Don’t confuse “odd” with funky node values: This is about…
The O(n) Club: Palindrome Number—Mirror, Mirror on My Integer (No Strings, No Magic)
The O(n) Club: Palindrome Number—Mirror, Mirror on My Integer (No Strings, No Magic) ⚡ TL;DR You want to check if a number looks the same…