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Python Python Collections (Retired) Slices Sorting Slices

Posted by Suresh Bollina
Suresh Bollina
Courses Plus Student 1,079 Points

silly_list=messy_list[:0:-3] silly_list=messy_list[len(messy_list):0:-3] not yielding correct answer

what is wrong with below code ?

lists.py 
messy_list = [5, 2, 1, 3, 4, 7, 8, 0, 9, -1]

# Your code goes below here
clean_list=messy_list[:]
clean_list.sort()
silly_list=messy_list[:0:-3]

1 Answer

Ian Keith
Ian Keith
15,720 Points
Ian Keith
Ian Keith
15,720 Points

Suresh,

You're close. Remember that slices are [Start : Stop : Step]. You are telling python to start at the 0 index, stop at the 0 index, and somehow give every 3rd number. Slices can also go backwards, so [-2] would give you the second item from the end.

Also remember the defaults. [:] gives you the entire slice, [0 : : 3] gives you from start to the end and give every 3rd item.

Hopefully that is enough hints to get you on the right track. You may also want to check out this python tutorial: (https://docs.python.org/3/tutorial/introduction.html)