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Andy Bosco
Courses Plus Student 681 Pointsreturns the first 4 and last 4 items in the iterable
This is challenging and so far I can't find anything on Google for Slicing the "first 4 and last 4 items in the iterable." What am I doing wrong?
def first_4(num):
return num[0:4]
def odds(odd):
return odd[1::2]
def first_and_last_4(filter):
return filter[3:-3:]
1 Answer
Michael Norman
Courses Plus Student 9,399 PointsIn the first part of the challenge you did first_4, so that part is complete. All we really need to worry about now is the last 4. You may remember that when we want the item at the end of a list, say my_list, can user
my_list[-1] # last element
my_list[-2] # next to last element
Using negative indices we can get the forth element from the end using an index of -4 and continue to the end of the list using a colon as before. Since lists are mutable we can concatenate the two and return that answer
def first_and_last_4(filter):
return first_4(filter) + filter[-4:]
Andy Bosco
Courses Plus Student 681 PointsAndy Bosco
Courses Plus Student 681 PointsThank you. I didn't know you can add the List together. Now I know.