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Start your free trialAlwen Nyikadzanzwa
1,541 Pointswhat's wrong with my code
this code is running well on my python idle but it's not accepted on the challenge
def first_4(item):
return item[:4]
def first_and_last_4(things):
al = things[:4] + things[-4:]
return al
def odds(numbers):
me = numbers[1::2]
return me
def reverse_evens(shalo):
ibu = shalo[::-1]
return ibu[0::2]
4 Answers
Steven Parker
231,275 PointsAfter reversing the list, which indexes were originally "even" will be based on the length of the list. It might work, but only half of the time.
Try slicing the even indexes first and then reversing them.
Timotheus Taruvinga
2,319 PointsHie! conditional branching will do you good here. check below:
def reverse_evens(shalo):
ibu = shalo[::-1]
if len(ibu)%2==0:
even=ibu[-2::-1]
else:
even=ibu[-1::-1]
return even
This really works
Steven Parker
231,275 PointsThere are two basic strategies for solving this task:
- extract the evens first and then reverse them
- compute the reverse starting position based on the even/odd-ness of the list size
Both methods work equally well when implemented correctly (but the first takes less code).
Timotheus Taruvinga
2,319 PointsYou are right Steve! Iwas just giving an extra suggestion for fun.
Timmie Nilsson
4,463 PointsNone of this thing works according to the code challange engine... I have been trying them out @ the workplace and there they work fine...
Steven Parker
231,275 PointsIt's easy to get a "false positive" working outside the challenge, either because of misunderstanding the objective, or testing with "easy data" that doesn't cover the same cases the challenge will.