Make a function named reverse_evens that accepts a single iterable as an argument. Return every item in the iterable wit

Question

@Kenneth Love
how to Make a function named reverse_evens that accepts a single iterable as an argument. Return every item in the iterable with an even index...in reverse.

For example, with [1, 2, 3, 4, 5] as the input, the function would return [5, 3, 1].

You can do it!

slices.py

def first_4(word):
    return word[0:4]
def first_and_last_4(test):
    return test[:4] + test [-4:]
def odds(word2):
    return word2[1::2]
def reverse_evens(reverse):
    return reverse[-1::-2]

Answer 1 · 2018-05-24T15:41:13Z

May 24, 2018 3:41pm

Hi Sanjay,

Try your code with inputs of both even length and odd length.

This challenge can't be completed with a single slice. Think about how you could solve it by getting halfway to the solution with a single slice, then performing another slice on that result to finish it off.

Cheers

Alex

Answer 2 · 2018-09-22T16:19:01Z

September 22, 2018 4:19pm

I was stucked for a little while with that one to. And then I remembered that there is difference when you count forward and when you count in reverse. What I am trying to say that when you count forward then when you start from 0 and go forward by every 2 indexes then you always will have a even index for example a[::2] but when you count in reverse then you start from the end and you need to remember that if the last index of list is not even then you have wrong answer for example if you have list a[1,2,3,4,5,6] and you count from the end trying to get even indexes by a[::-2] then you will have [6,4,2] and they are in indexes 5, 3, 1 who are not even so you need expect that user can give you lists with even or odd total list lenght and you need use if function for both of them.

My solution was: def reverse_evens(a): if len(a) % 2 == 0: a1 = a[1::-2] else: a1 = a[::-2] return a1

I am not perfect in english since it is not my first language so sorry if I made some mistakes in my text or if my explanation was not clear enough.

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Sanjay Devadkar

Sanjay Devadkar

Make a function named reverse_evens that accepts a single iterable as an argument. Return every item in the iterable wit

2 Answers

Alex Koumparos

Alex Koumparos

Ernestas Petruoka

Ernestas Petruoka