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Python Python Collections (2016, retired 2019) Slices Slice Functions

Posted by Darrin Spell Jr
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Darrin Spell Jr
Full Stack JavaScript Techdegree Student 10,303 Points

Can someone explain to me what exactly I am doing wrong in this challenge. It's pretty tricky.

I am having a hard time with task 2 with first_4 and last_4

slices.py 
def first_4(string):
    return string[:4]

def first_and_last_4(numbers):
    numbers = list(range(20))
    first_4 = numbers[:4]
    pre_4 = numbers[-1:-5:-1]
    last_4 = pre_4[::-1]
    all_4 = first_4 + last_4
    print(all_4)

1 Answer

Steven Parker
Steven Parker
241,811 Points
Steven Parker
Steven Parker
241,811 Points

You're working too hard! You already know how to get the first 4 with one line of code. Getting the last 4 is very similar (just with different slice arguments). Then it's just a matter of sticking them together and returning (and no lists or ranges needed).

Darrin Spell Jr
.a{fill-rule:evenodd;}techdegree
Darrin Spell Jr
Full Stack JavaScript Techdegree Student 10,303 Points

I don't know how to stick two different slices together.

Steven Parker
Steven Parker
241,811 Points
Steven Parker
Steven Parker
241,811 Points

Joining strings is done with concatenation, using the plus-sign operator ("+").