Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Python Python Collections (2016, retired 2019) Slices Slice Functions

Kyle Petran
Kyle Petran
5,017 Points
Posted by Kyle Petran
Kyle Petran
5,017 Points

Fairly certain my answer gives the proper return

why isn't reverse_evens ( ) working?

slices.py 
def first_4(itera):
    return itera[:4]
def first_and_last_4(itera):
    return itera[:4]+itera[-4:]
def odds(itera):
    return itera[1::2]
def reverse_evens(itera):
    return itera[len(itera)-1::-2]

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

It might work for some test cases. But to work in all cases it needs one of two possible strategies:

  • compute the starting position based on the length of the array, or
  • extract the even indexes first, and then reverse them in a separate operation