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Python Python Collections (Retired) Slices sillyCase

I am getting error "slice indices must be integers or None or have_index_method.. Can someone help me figure out why?

I'm sure this has to do with my start stop and step in my slices so any help fixing this would be great.

silly.py
# The first half of the string, rounded with round(), should be lowercased.
# The second half should be uppercased.
# E.g. "Treehouse" should come back as "treeHOUSE"

def sillycase(string):
  first_half = string[0:len(string) -1 / 2]
  first_half.lower()
  last_half = string[len(string)-1:len(string)/ 2 + 1: -1]
  last_half.upper()
  return first_half + last_half

2 Answers

Martin Cornejo Saavedra
Martin Cornejo Saavedra
18,132 Points

You didn't round it, if you don't round, then the operation outputs a double, not an integer.

def sillycase(string):
  index = 
  first_half = string[0: round(len(string) / 2)]   #use round(), and don't use len() - 1 its not necessary
  first_half.lower()
  last_half = string[round(len(string) / 2) : len(string)] 
  last_half.upper()
  return first_half + last_half
Jariel Arias
Jariel Arias
1,549 Points

But in python doesn't any whole number divided by 2 give you a rounded whole number automatically? Every time I've tried it it has worked :/

Yes, Python automatically rounds answers with dividing. Odd numbers divided by 2, will give remainder, but will be rounded in the result. Looks like the problem is the -1.