The nested for loop—a simple yet indispensable tool for solving algorithmic problems. Whether you’re tackling dynamic programming, matrix traversal, or brute force solutions, nested for loops are often the backbone of success on LeetCode. They allow us to compare elements, generate combinations, and explore relationships within data—key actions for solving…
Number of 1 Bits – 191. LeetCode
Counting the number of 1 bits in a binary number (also know as the Hamming Weight) is a fundamental problem in computer science. It’s a basic operation often used in error detection, network routing, cryptography. The task is simple: given an integer, count how many bits are set to 1…
The Ultimate Guide to Prefix Sum: Algorithm Patterns Simplified
If you’ve ever solved a problem that required adding up parts of an array or finding the sum of a subarray multiple times, you know how tedious it can get. What if there were a way to do it in a snap? Prefix sum is the algorithmic shortcut you didn’t…
Backtracking Demystified: The Algorithm Pattern That Powers Problem Solving
Backtracking is a powerful and versatile algorithmic technique used to solve problems that require exploring all possible solutions while eliminating unpromising paths along the way. It works by incrementally building candidates for a solution and abandoning those that fail to satisfy the problem’s constraints. Think of it as navigating a…
Mastering the Top-K Algorithm Pattern: A Step-by-Step Guide
In the world of algorithms, the Top-K pattern stands out as one of the most versatile and practical techniques. Whether you’re ranking search results, analyzing data trends, or solving complex coding problems, the Top-K algorithm pattern is your go-to strategy. This blog will walk you through a structured framework to…
Simplify Algorithm Design with the Monotonic Stack Pattern
When solving sequence-based problems—like finding the next greater element, stock span, or calculating sliding window maximum—efficiency is paramount. Many of these problems involve comparing elements across a sequence, and a brute-force approach often leads to nested loops with a costly O(n^2) time complexity. Enter the monotonic stack: a powerful data…
Frequency Counters 101: The Algorithm Pattern You Need to Know
The Frequency Counter pattern is a fundamental algorithm design approach used to solve problems by counting occurrences of elements in an efficient way. It replaces the need for nested loops (brute-force methods) with hash maps or dictionaries to reduce time complexity. Here’s a structured framework to learn and master this…
Greedy Patterns in Algorithms: Simplify, Solve, Succeed
Greedy algorithms are a powerful approach for solving optimization problems, where the goal is to find the best solution under certain constraints. The concept is simple: make decisions step-by-step, always choosing the option that looks best at the moment, and hope it leads to the best overall solution. How Greedy…
Why K-Way Merge is the Algorithm Pattern You Need to Know
If you’ve ever faced a problem involving multiple sorted arrays or lists that need to be combined into one sorted result, you’ve encountered a k-way merge scenario. It’s an essential algorithmic technique, powering systems like search engines, data processing pipelines, and distributed databases. In this post, we’ll break down the…
Kth Largest Element in a Stream – 703. LeetCode
Imagine you are continuously receiving numbers in a stream, and you want to keep track of the Kth largest element at any given time. This means if you are given a number k, you need to find the k-th largest element among all the numbers you have received so far….
