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# Need help creating oddNumbers array in closures challenge.

Hi Everybody,

I am having difficulty creating the oddNumbers array in the second step of the following code challenge:

Given an array of integers, called numbers, use the filter function (and the helper function we created) to create a new array containing only odd numbers. Assign this new array to a constant named oddNumbers.

When the isOdd Function returns the boolean values, how do I convert them to Integer values for the new array? Does it automatically return integers because it filters the numbers array?

I need help completing this challenge! Thanks for the help.

filter.swift
```let numbers = [Int](0...50)

func isOdd(i: Int) -> Bool {
return i % 3 == 0
}

let oddNumbers = numbers.filter(Int, isOdd)
```

Hey Matt, I think the problem came when you completed the first challenge wrong. The isOdd function should "return i % 2 != 0" instead of " return i % 3 == 0"

And to pass the last test, you need to pass in the function isOdd as a parameter to filter, therefore "Int" can be removed from your code.

```func isOdd(i: Int) -> Bool {
return i % 2 != 0
}

let oddNumbers = numbers.filter(isOdd)
```

Should work now :D

Does the Bang "!" operator unwrap the boolean values to return integers in the array?

let numbers = [10,423,802,765,943,12,405,230,1348,128,237] let oddValues = numbers.filter {\$0%2 != 0}

Hi Matt, good to know it worked for you.

The reason I'm using "i % 2 != 0" is to say any number divided by 2 isn't equal to 0, which in other terms means it's an odd number. Using "i % 3 == 0 " may work for some odd numbers however it is not consistent across the entire array and will create mistakes. A quick example

let array = [1,2,3,4,5,6,7,8,9]

let filteredArray = array.filter { \$0 % 3 == 0}

filteredArray // -> 3,6,9 (and number 1 is missing)

Check this link (https://developer.apple.com/library/prerelease/ios/documentation/General/Reference/SwiftStandardLibraryReference/Array.html) Very useful to understand the array function in Swift.

Thanks for the feedback John DiPanfilo :) . Glad I could help. Have a good day