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Python

Posted by Chapman Cheng
.a{fill-rule:evenodd;}techdegree seal-36
Chapman Cheng
PHP Development Techdegree Graduate 46,936 Points

[Reverse Evens] My code works, but cannot past test

The Question: 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].

so here's my code, I do it in workspace first to test out, it works, but I couldn't get past test, what's the problem? thanks in advance 

list = [1,2,3,4,5,6,7,8,9,10]

def reverse_evens(x):
    if x[-1]%2==0:
        return x[-1:0:-2]
    else:
        return x[-2:0:-2]

2 Answers

Kirsten Smith
Kirsten Smith
3,484 Points

You need to return every item with an even INDEX. You are currently checking if the actual number is even. For example, regardless of what the numbers are, if the list is [3, 5, 7, 9, 2, 9], the index values are [0, 1, 2, 3, 4, 5], those are what you need to be concerned about, not if the actual number is even.

Chapman Cheng
.a{fill-rule:evenodd;}techdegree seal-36
Chapman Cheng
PHP Development Techdegree Graduate 46,936 Points

oh you're right, i looked past the index, mixed up thanks alot

Adam Paciorek
Adam Paciorek
3,181 Points
Adam Paciorek
Adam Paciorek
3,181 Points

Hello,

I have a problem here as well.

My function is :

def reverse_evens(list):
    reversed_list = list[::-1]
    return reversed_list[::2]

and gets a correct output for [1, 2, 3, 4, 5] but does not pass the test...

Kirsten Smith
Kirsten Smith
3,484 Points

try this check again with a list that contains an even number of values, you will see you don't get back the correct result. you need to alter the code to work for both even and odd sets of data.