aparently... event though [-1::-2] returned the same values as [::2][::-1] ....it was incorrect...

Hello!

So the meat of challenge 4 is: Return every item in the iterable with an even index...in reverse.

Given the list: [1, 2, 3, 4, 5], we want the following indexes: 0, 2, and 4. Our list would become [1, 3, 5]. Reversed, this is [5, 3, 1]. Your code works great for this example!

But what if our list is not an odd length. What if we had [1, 2, 3, 4, 5, 6] for example? We want the following indexes: 0, 2, and 4. Our list would become [1, 3, 5] then reversed to [5, 3, 1].

Here is where your code presents a problem.

>>> x = [1, 2, 3, 4, 5]
>>> y = [1, 2, 3, 4, 5, 6]

>>> x[-1::-2]
[5, 3, 1]
>>> y[-1::-2]
[6, 4, 2]

Your code starts at the last index, not at the last even index. In order to solve this, I would suggest separating it into 2 list commands (mylist[...][...]), one to get the even numbers and one to reverse the list.

I hope this helps! If you still don't understand anything, feel free to reply :)

(From my post yesterday: https://teamtreehouse.com/community/reverseeven)