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Python Python Collections (Retired) Slices Slice Functions

Manfredi Martorana
Manfredi Martorana
19,470 Points
Posted by Manfredi Martorana
Manfredi Martorana
19,470 Points

Slicing

Hi, I don't understand how to complete Python Slicing Challenge. In particular I don't know how to slice the first 4 and the last 4 elements of a list.

Thanks for the help ;)

eugeneteo
eugeneteo
112 Points

Hi Manfredi,

Take a look at the following two examples. I hope this will help you understand slicing better.

>>> a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
>>> len(a)
10
>>> a[len(a) - 4:] # a[6:len(a)]
[7, 8, 9, 10]
>>> a[-4:] # Another way!
[7, 8, 9, 10]
>>> a[:4] # a[0:4]
[1, 2, 3, 4]

>>> str[:4]
'hell'
>>> str = 'hello world'
>>> str[:4] # First 4, you can also specify str[0:4]
'hell'
>>> str[-4:]
'orld'

Eugene

3 Answers

Manfredi Martorana
Manfredi Martorana
19,470 Points
Manfredi Martorana
Manfredi Martorana
19,470 Points

Well, I don't know how to write a function that accept a list, and return the first and last four elements.

Thank you

Manfredi

eugeneteo
eugeneteo
112 Points

I have not worked on that challenge, but I think this is what you are asking:

>>> def sublist(lst):
...   return # add your slicing code here
... 
>>> sublist(str)
('hell', 'orld')
>>> sublist(a)
([1, 2, 3, 4], [7, 8, 9, 10])

Eugene

Manfredi Martorana
Manfredi Martorana
19,470 Points
Manfredi Martorana
Manfredi Martorana
19,470 Points

Perfect... One last thing: the output must be in the same bracket!

Manfredi

eugeneteo
eugeneteo
112 Points

Try to work on the answer. You are almost there with these hints. Good luck!