# SKB – Scala Set

## 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 Set.

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 Set !

We saw other data structures in previous SKB like `List` or `Map`.

Let’s look at `Set`.

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 (Xnga8KMIQimJPP8BwT5VAQ).

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

Did you notice that `Set` cannot contain duplicate values? A `Set` is a list of unique values.

When you combine the two `Set`, it removes the duplicated values and only keep one of each.

One thing to know is that `Set` do not guarantee consistant ordering. You should not rely on index of the elements. If you want to learn more, you can read this great answer on Stackoverflow.

Last thing about `Set` is that it has all the same function as `List` such as `map`, `flatMap`, `filter`, etc…

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

## Conclusion

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