find-array-union()

Step 1: Understanding the Problem

In this step, our goal is to find the union an array in Swift. The 'union' of two or more arrays refers to a set that comprises items present in any of the given arrays.

Let's start by declaring two arrays that we want to find the union of:

let array1 = [1, 2, 3, 4, 5]
let array2 = [4, 5, 6, 7, 8]

Step 2: Create a Set from Arrays

We'll first start with converting each array into a set. A set is a built-in data type in Swift to store distinct elements in no particular order.

let set1 = Set(array1)
let set2 = Set(array2)

Step 3: Using the Union Method

Once we have these sets, we are ready to find their union. Swift set types have a union() method that can be used for this purpose:

let union = set1.union(set2)

Step 4: Convert Union back to Array

Finally, we can convert the result back to an array using the array initializer.

let arrayUnion = Array(union)

Step 5:Write all into one Function

The final step is to write all these steps into one Swift function. It should accept two arrays and return their union:

func findUnion<T: Hashable>(array1: [T], array2: [T]) -> [T] {
    let set1 = Set(array1)
    let set2 = Set(array2)
    let union = set1.union(set2)
    return Array(union)
}

This function uses Swift generics to make it work with any type of array (as long as the array's element type conforms to the Hashable protocol).

And that's it! We now have a reusable function that computes the union of two arrays in Swift.