My Tryst with CS

 I came across this excellent video, explaining how the SHA-256 algorithm works internally. I had always been excited to understand how a real-world hashing algorithm works internally. SHA-256 is one of the most popular hashing algorithms, so after getting my hands on that video, I knew I had to try and implement this on my own. This feels like once in a lifetime opportunity. So here I am after having implemented the algorithm on my own and feeling confident understanding how SHA-256 works. I want to pass on that same confidence to the readers of this blog (probably including me in a few months :D) along with code snippets. So, lets dive right into it... Basic Operations There are some basic operations that the SHA-256 algorithm builds on top of. Here is a list of those: 1. Shift Right  - Shifts the bits of the original number pos bits to the right, dropping of things that slide of the end. 2. Rotate Right  - Rotates pos bits in the original number. Very similar to shift but instead o

 I have been meaning to write this blog for some time now but somehow kept on postponing (read procrastinating...). I read about this technique of Consistent Hashing a while back and was mesmerized by its elegance. Recently read it again in this brilliant blog and thought of expressing it in my own words for posterity. So let us begin. Hashing I won't talk too much about hashing since it is a very basic computer science concept. In a word, it means mapping an object to another object. Or more generally, mapping a key to a value where their types don't matter. Mostly the mapping is from a string to int.  There could be multiple different hash functions that can exist which randomize the how the keys are hashed to the values. We are going to consider a simple use case where let's say you have N different servers and there are multiple keys that you want to distribute among those servers. How do you do it? Well, a simple strategy is that you have a function which applies some