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Python Python Collections (Retired) Slices Slice Functions

Posted by Ryan Lail
Ryan Lail
4,386 Points

Make a function name first_and_last_4 that accepts an iterable and returns the first 4 and last 4 items in the iterable.

I don't understand how to get both slices to output

slices.py 
def first_4 (iterable) :
  return iterable[:4]

def odds (iterable) :
  return iterable[1::2]

def first_and_last_4 (iterable) :
  return iterable[:4][-4:]

2 Answers

David McCarty
David McCarty
5,214 Points

You can concatenate them I believe.

You can do this like so:

def first_and_last_4(iterable):
    return iterable[:4] + iterable[-4:]

You need to call the iterable object twice instead of doing iterable [:4][-4:]

Chris Grazioli
Chris Grazioli
31,225 Points
Chris Grazioli
Chris Grazioli
31,225 Points

Thanks for the simplicity! Did the video cover any of the concatenation?

akak
akak
29,445 Points
akak
akak
29,445 Points

I would do it like this:

def first_and_last_4 (iterable):
  result = iterable[:4] + iterable[-4:]
  return result