Scala CMC: Implement zipWith (Scastie with the signature to start out with)
(ignore the error, hit "Clear messages" to git rid of it. Use Ctrl+S or the Run button to save and run)
Actually, that's not a very good challenge to start with
Slightly better starting CMC: Write a safe head function that gives the first element of a list wrapped in a Some if it's nonempty and a None if it's empty
That's because of 0 to list1.length. to makes an inclusive range, so it tries to access the element at index 3, which doesn't exist because there's only 3 elements in the list. You could try either 0 to list1.length - 1 or 0 until list1.length instead
You don't need semicolons, and list3 doesn't have to be a var
But you can use a for comprehension instead. Also, Arrays are mutable and hard to print, so let's avoid those
Here's a horribly inefficient but fun version using pattern matching that also works with lists of different sizes (it trims to the size of the shorter list)
