find-array-intersection()

Step 1: In memory, Initialize Two Arrays

First, we'll initialize two arrays whose intersection we're going to find. Let's call these arrays Array1 and Array2.

let array1 = [1, 2, 2, 1]
let array2 = [2, 2]

Step 2: Transform Arrays into Sets

Since we're only interested in the unique values that appear in both arrays, we'll first turn Array1 and Array2 into sets. In Swift, this is accomplished using the Set object. Moreover, since a set won't include duplicate values even if they are present in the array, it helps us in dealing with repeated elements in an array.

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

Step 3: Find the Intersection of the Sets

Using the intersection method, we can find the common values between set1 and set2. This returns a new set with just these values.

let intersection = set1.intersection(set2)

Step 4: Convert the Intersection Set Back Into an Array

The Array initializer can be used to change our intersection set back into an array.

let intersectionArray = Array(intersection)

Conclusion

The final implementation combines all of these steps into a single function. Below is the full code implementation of the function to find the intersection of two arrays:

func findArrayIntersection(array1: [Int], array2: [Int]) -> [Int] {
    let set1 = Set(array1)
    let set2 = Set(array2)
    let intersection = set1.intersection(set2)
    return Array(intersection)
}
let result = findArrayIntersection(array1: [1, 2, 2, 1], array2: [2, 2])
print(result) // Outputs: [2]

This function, findArrayIntersection, takes in two integer arrays and returns their intersection as a new array. By using the Set object in Swift, we can easily find unique common elements between two arrays. }