The O(n) Club: Maximum Sum Circular Subarray Madness
The O(n) Club: Maximum Sum Circular Subarray Madness ⚡ TL;DR If you’ve ever dreamed of wrapping your arrays like burritos, here’s…
The O(n) Club: Predict the Winner’s Game—Why Dynamic Programming Always Wins (and Greedy Moves Cry in the Corner)
The O(n) Club: Predict the Winner’s Game—Why Dynamic Programming Always Wins (and Greedy Moves Cry in the Corner) ⚡ TL;DR It’s two coders, one…
The O(n) Club: Conquer Subarrays with Exactly K Distinct Integers (Before Coffee Runs Out)
The O(n) Club: Conquer Subarrays with Exactly K Distinct Integers (Before Coffee Runs Out) ⚡ TL;DR Counting subarrays with exactly K distinct…
The O(n) Club: Power of Two — Bitwise Magic and the Ancient Single-Bit Prophecy
The O(n) Club: Power of Two — Bitwise Magic and the Ancient Single-Bit Prophecy ⚡ TL;DR Don’t know if your number is a power of two? Skip the…
The O(n) Club: Keys and Rooms—How to Unlock a Mansion Without Losing Your Mind (or Your Java Stack)
The O(n) Club: Keys and Rooms—How to Unlock a Mansion Without Losing Your Mind (or Your Java Stack) ⚡ TL;DR You wake up in room 0 of a…
The O(n) Club: Integer to Roman – How to Greedily Conquer Antiquity with Java
The O(n) Club: Integer to Roman – How to Greedily Conquer Antiquity with Java ⚡ TL;DR Need to translate boring numbers into Roman numerals for…
The O(n) Club: Smaller Numbers Than You (and Other Ego Checks)
The O(n) Club: Smaller Numbers Than You (and Other Ego Checks) ⚡ TL;DR Need to count how many numbers are strictly smaller than each item in…
The O(n) Club: How Pivot Index Became the Therapist Arrays Never Knew They Needed
The O(n) Club: How Pivot Index Became the Therapist Arrays Never Knew They Needed
The O(n) Club: Average of Levels in a Binary Tree (Or Why Java Hates Decimals)
The O(n) Club: Average of Levels in a Binary Tree (Or Why Java Hates Decimals) ⚡ TL;DR For each level of your binary tree, don’t…
The O(n) Club: 4Sum II — When Hashmaps Save You from Loop Purgatory
The O(n) Club: 4Sum II — When Hashmaps Save You from Loop Purgatory ⚡ TL;DR Given four integer arrays, count (i, j, k, l) such that nums1[i] +…