woooow)

yes i did that ^^

The way you used modulo operator to know the number is integer or not is a nice way to me, now I knew a new thing for today. Thanks :)

_ is often used as a variable that's unused (Other than in Lodash), it's just a variable name that doesn't really have a name.

Hiii...
What is the use of _ in (_,i)? Please explain.

If you have a look at the first line of the function, you will know.

The only "new" thing here is the arrow function. The rest probably worked in the very first version of the language.

This language gets dirtier each day.

The problem was that in the examle code you used farthestDistance, but the tests expected furthestDistance instead. This is misleading a bit.

That's why he uses COUNT(s) instead of SUM(s)

This one times out for me.

I think it has been not corrected in the tests.

Is it the same algorithm that strrev uses? Is there a site where I can check the algorithms behind core functions?