Template literals FTW

This is good self documenting code, but I'd say the last line is completely unnecessary. Noting the sum and average is good practice enough.

i think so yes

This is great!

very nice

Yeah, that's right bro

I like this solution because it's readable

The best explanation of filter I have found, online resources just werent making sense to me.

damn dude, do u know how "if" works?

od

Shouldn't be any issue with modifying the given parameter as we are told that we "can assume that all inputs are valid integers".

From MDN:
"Parameters are essentially passed to functions by value — so if the code within the body of a function assigns a completely new value to a parameter that was passed to the function, the change is not reflected globally or in the code which called that function.

When you pass an object as a parameter, if the function changes the object's properties, that change is visible outside the function."

reducer can take up to 4 arguments, you can just omit the last two, which are indices and array. So you can use acc and value of the index.