Guess the JavaScript Output: Level impossible!

This post is part of a series called Guess the JavaScript Output
If you like to read Part 1 of the series, see here

So, without any ado, let’s get to it:

Today’s question(Super tricky):

What does console.log((! + [] + [] + ![]).length) output in JavaScript?

Big Mike solved this in 2 minutes. Can you beat big Mike on this one?

And Yes, JavaScript is officially crazy!