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Start your free trialKudakwashe Ngoma
2,303 PointsCode Challenge: reverse_evens
How do i return the items with an even index, in reverse
def first_4(item):
return item[0:4]
def first_and_last_4(item):
slice1 = item[0:4]
slice2 = item[-4:]
return slice1 + slice2
def odds(item):
return item[1::2]
def reverse_evens(item):
reversed(item)
return item[::-2]
3 Answers
Chris Freeman
Treehouse Moderator 68,428 PointsIt can not be done in a single slice since the length of the list is unknown. You need to either use an if
statement on the length of the argument, or use a slice of a slice where the first slice gets the evens then the second slice reverses it.
You can use the notation item[ ][ ]
to slice a slice.
Post back if you need more help. Good luck!!!
<noob />
17,062 PointsTry item[-1::2]
Kudakwashe Ngoma
2,303 PointsI tried it, but it's "not returning the right values", whatever that really means
Kudakwashe Ngoma
2,303 PointsGot it now, it worked..... thanks a lot Chris Freeman
Kudakwashe Ngoma
2,303 PointsKudakwashe Ngoma
2,303 Pointsdef reverse_evens(item): return item[2::][::-1]
am still not getting the answer. How do i put thru the if statement?
Chris Freeman
Treehouse Moderator 68,428 PointsChris Freeman
Treehouse Moderator 68,428 PointsYour first slice is close but it is selecting all elements starting with the second index. You need this
step
to be 2, not the starting index.