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Code challenge lists - improving my solution [solved]

#1

Heyo, I was wondering if you could help me understand this:

My initial attempt was to try and .pop the first (0th?) element from the list, using the following code:

def delete_starting_evens(lst):
i = 0
while lst[i] % 2 == 0:
lst.pop(i)
return lst

Which works for list#1. I quickly realized I had been a bit too eager, though, having proceeded without fully reading the exercise - it needs to work even if every element is even. So I came up with:

def delete_starting_evens(lst):
  if len(lst) > 0:
    i = 0
    while lst[i] % 2 == 0:
      lst.pop(i)
    return lst
  else:
    return lst

but this throws a tab error. To my naive mind it seems as if the lines are correctly indented? I had to edit my code a couple times when pasting it here as it came out with different indentations than in my script (a clue!), which I promptly changed and ran again to no avail.
What am I missing here?

FAQ: Code Challenge: Loops - Delete Starting Even Numbers
#2

Will this line raise an error when the list is empty?

Do we even need a variable, i?

while lst[0] % 2 == 0
    lst.pop(0)
#3

Hm, so I was hoping “if len(lst) > 0:” would handle the empty list;
as for the i variable, I was thinking it would be necessary for the .pop(i) but I take it from your reply .pop(0) will do the same job

1 Like
#4

It will catch it on the inputs, but not in the loop.

#5

Aah gotcha, so after the popping commences it won’t kick in. I’ll try and adapt it. Thanks for the help!

1 Like
#6 
def delete_starting_evens(lst):
  if len(lst) > 0:
    while lst[0] % 2 == 0:
      lst.pop(0)
      if len(lst) == 1:
        return lst
    return lst
  else:
    return lst

totally worked! Thank you! Not so pretty perhaps but hey, satisfying af

#7

What if that line returns a list with an even number in it?

#8

…back to the drawing board

1 Like