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iOS Closures in Swift 2 Building Standard Library Functions Using Filter

Apply the filter function on the numbers array provided to end up with an array of odd numbers. Assign the value to a

Need Help I don't know what to do, or how to solve this questions

filter.swift
let numbers = [10,423,802,765,943,12,405,230,1348,128,237]let numbers = [Int](0...50)

// Enter your code below

func isOdd(i: Int) -> Bool {
if i % 2 == 0 {
return false
} else {
return true
}
}

let numbers = [1,2,3,4,5]
let oddNumbers = numbers.map { isOdd }

1 Answer

David Papandrew
David Papandrew
8,386 Points

You want to use filter to solve this problem. The result is a much simpler (less verbose) solution to the alternative which would be to loop through the array and append the array values that are odd to a new array.

Your function isn't that far off. But instead of creating a standalone function, you'll include the function logic in the closure for the filter method.

Here's the solution:

let numbers = [10,423,802,765,943,12,405,230,1348,128,237]

let oddValues = numbers.filter { $0 % 2 == 1 }