August 16th, 2013, 12:58 PM

Ebook question help needed
im having trouble with this exercise.
Exercise 10.2 Write a function called chop that takes a list and modifies it, removing the first and
last elements, and returns None.
Then write a function called middle that takes a list and returns a new list that contains all but the
first and last elements.
I think I can do the second part, I came up with
Code:
t=[1,2,3,4]
def middle(t):
return t[1:len(t)1]
print(middle(t))
The first part has me stumped tho, I came up with this
Code:
t=[1,2,3,4]
def chop(t):
del t[0:len(t)1]
print(chop(t))
It returns None but it doesn't look right and im not sure that this is what the question is asking for. Some advice would be appreciated.
August 16th, 2013, 02:29 PM

Useful trick: Index from the right end
[code>>> t=[1,2,3,4]
>>> def chop(t):
del t[0], t[1]
# or
# del t[0]
# del t[1]
>>> chop(t)
>>> t
[2, 3]
>>> def middle(t):
return t[1:1]
>>> middle(t)
[]
>>> [/code]
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