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

Ionut Dragan
Ionut Dragan
1,696 Points
Posted by Ionut Dragan
Ionut Dragan
1,696 Points

Task 4 of 4 slices.py: Didn't get the right values from `reverse_evens`.

Hello there.

Ive tested this on my terminal and I got the right values from the reverse_evens function. Dont understand what is the problem there.

Here is my code:

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

def last_4(value):
    return value[-4:]


def first_and_last_4(value):
    return first_4(value) + last_4(value)


def odds(value):
    return value[1::2]

def reverse_evens(value):
    return value[-1::-2]

1 Answer

Ionut Dragan
Ionut Dragan
1,696 Points
Ionut Dragan
Ionut Dragan
1,696 Points

Solved with:

def reverse(value):
    return value[::2][::-1]
Gerald Wells
Gerald Wells
12,763 Points

A little late responding, but that is perfect! First you get every even index with [::2] and reverse it with [::-1]. This is exactly why Python is my favorite language. without having to iterate through an array you can get all values that are located at an even index. In C you would have to set a variable to iterate through a for loop and output each value if the index%2 ==0 and blah blah. Guido van Rossum is a God! or is he God? Python is the only Miracle I have ever seen.