This is art

Beautiful, simple and efficient.

Recursion 🤘

Recursion 🤘

Your answer is an array of strings while the expected output should be an array of integers

Thank you both of you. I'll definitely have a look. Already learned a lot here.

It's the same thing for every katas: you need to write a function that solves the task, tests call your function and check it does the job correctly. If you are not familiar with how Codewars works, you should have a look at the documentation (Chrono79 gave you the link). However, not a kata suggestion.

Your function is called by the tests, read this: https://docs.codewars.com/getting-started/solving-kata to get how Codewars works.

That's because, as a beginner, I've that you should call the function you created in order to get the return.

The input is passed through the argument, and where do you see you should call the function yourself?

The instructions should be rephrased. You actually don't need to get an input or call the function.