Swift Program to Find Largest Element of an Array

1. Introduction

Finding the largest element in an array is a common computational task. Arrays in Swift can hold multiple values of the same type. In this tutorial, we'll demonstrate how to find the largest number in an array of integers using Swift.

2. Program Overview

We will:

1. Define an array of integers.

2. Determine the largest element from the array.

3. Print the largest element.

3. Code Program

// Function to find the largest element in an array
func findLargestElement(_ arr: [Int]) -> Int? {
    // Check if the array is empty
    guard !arr.isEmpty else {
        return nil

    var largest = arr[0]  // Initialize largest with the first element

    // Iterate through the array starting from the second element
    for i in 1..<arr.count {
        if arr[i] > largest {
            largest = arr[i]  // Update largest if a bigger number is found

    return largest

// Testing the function
let numbers = [3, 8, 1, 45, 27, 5]
if let result = findLargestElement(numbers) {
    print("The largest element of the array is: \(result)")
} else {
    print("The array is empty.")


The largest element of the array is: 45

4. Step By Step Explanation

1. The function findLargestElement(_:) is defined to determine the largest element of an integer array. It returns an optional integer to handle the possibility of an empty array.

2. Inside the function:

- We first check if the array is empty using the guard statement. If it's empty, the function returns nil.- The variable largest is initialized with the first element of the array.- Using a for loop, we iterate through the array starting from the second element. If we encounter an element larger than the current value of largest, we update largest with the new value.

3. After iterating through all the elements, the function returns the value of largest.

4. To demonstrate the function, we define an array numbers and call the findLargestElement(_:) function. The result, if available, is then printed out.

This approach provides an efficient way to locate the largest element in an array in Swift.