# SKB – Scala Comparators

## Introduction

Periodically, I will publish new exercises so you can slowly build up knowledge about Scala.

It is designed to be done in a very short amount of time and learn a little bit each day, just to create a routine.

This episode will teach you about Scala Comparators.

Hope you are going to enjoy it! It is designed for anyone to learn Scala from scratch and slowly learn, one Bit at a time.

After this Bit, I would love to hear your feedback in the comments down below.

Feel free to join the Discord server as well if you would like some help and support from the rest of our community.

## What are we learning today?

Today we are going to learn about Scala Comparators !

A few new concepts are needed for this SKB.

First, what is a `Boolean`? A `Boolean` can only take two values: `true` or `false`. It is the result of a mathematical question. For instance, is 2 less than 5 (`2 < 5`), it would returns "yes" (`true`).

And from previous SKB, you might have noticed that `assert` tests if what is inside is `true`.

Time to try on the exercise on your own and scroll down for more information when you are done or if you are stuck.

## Exercise

Here is an exercise to complete today.

If I did my job well, you should be able to guess by yourself the solution based on what you previously learned and based on the clues.

The goal of the exercise is to replace the `???` by a piece of code so that the exercise compiles and that's how you win! Good luck!

You can fill the exercise right in here:

Or, if it does not load, go on to Scastie (5MhccpxLQiSzOQ8CWjqjwQ).

In this exercise you will learn (or have learned, if you have already solved the puzzle) about Scala Comparators.

In Scala, and in the majority of other programming languages, you have a series of built-in comparators for mathematics:

• `==` : for equality. Some tips here:
• Notice that there are two `==`. With only one `=`, it would be an assignation (Like in: `val a = 2`).
• In your projects as a software engineer, always be careful about comparing numbers with decimals (Like `1.5632426546`, they are called `Double` or `Float`) because the computer will round those numbers. So instead of `a == b`, you should be doing something like: `Math.abs(a - b) < 0.01`.
• `!=` : Not equal
• `>` : Greater than
• `<` : Less than
• `>=` : Greater than or equal
• `<=` : Less than or equal

Feel free to go back to the exercise, modify the code to try out new things and get a better intuition for Scala Comparators.

## Conclusion

I hope you have learned something new or had fun during this Scala Knowledge Bit.