How to change icons in bootstrap?

Question

JavaScript

I want to make the icon change when clicked, then in bootstrap I need to replace a certain class, but I don’t understand how to make it so that when clicked, replace it and insert another icon
https://jsfiddle.net/hollanditkzn/ena42bod/24/

Answer 1

https://jsfiddle.net/ena42bod/28/

Answer 2

https://jsfiddle.net/dbunt1tled/ena42bod/31/