How to Find the Largest Element in an Array in PHP?

Given an array containing some elements, the task is to find the largest element from an array in PHP. PHP provides several ways to achieve this, each with its own advantages and use cases.

Below are the approaches to find the largest element in an array in PHP:

Using max() Function

The max() function is a built-in PHP function that returns the largest value from an array or a set of values.

Example: This example shows the use of the above-mentioned approach.

<?php

// Declare an array
$arr = [10, 20, 30, 40, 50];

// Find the largest element
// using max() function
$largest = max($arr);

echo "The Largest Element is: " . $largest;

?>

Output

The Largest Element is: 50

Explanation:

• $arr is the array containing the elements.
• max($arr) returns the largest value in the array.

Using a Loop

You can use a loop to iterate through the array and find the largest element manually. This approach is more flexible and can be used when additional logic is required.

Example: This example shows the use of the above-mentioned approach.

<?php

// Declare an array
$arr = [10, 20, 30, 40, 50];

// Initialize the largest variable
$largest = $arr[0];

// Iterate through the array to 
// find the largest element
foreach ($arr as $value) {
    if ($value > $largest) {
        $largest = $value;
    }
}

echo "The Largest Element is: " . $largest;

?>

The Largest Element is: 50

Explanation:

• $arr is the array containing the elements.
• $largest is initialized with the first element of the array.
• The foreach loop iterates through each element in the array.
• If the current element is greater than $largest, update $largest.

Using sort() Function

The sort() function sorts the array in ascending order. After sorting, the largest element will be the last element in the array.

Example: This example shows the use of the above-mentioned approach.

<?php

// Declare an array
$arr = [10, 20, 30, 40, 50];

// Sort the array
sort($arr);

// The largest element is the 
// last element after sorting
$largest = $arr[count($arr) - 1];

echo "The Largest Element is: " . $largest;

?>

The Largest Element is: 50

Explanation:

• $arr is the array containing the elements.
• sort($arr) sorts the array in ascending order.
• The largest element is the last element of the sorted array, accessed by count($arr) - 1.

Using reduce() with Anonymous Function

The array_reduce() function iteratively reduces the array to a single value using a callback function.

Example: This example shows the use of the above-mentioned approach.

<?php

// Declare an array
$arr = [10, 20, 30, 40, 50];

// Find the largest element using
// array_reduce() function
$largest = array_reduce($arr, function($carry, $item) {
    return ($item > $carry) ? $item : $carry;
});

echo "The Largest Element is: " . $largest;

?>

The Largest Element is: 50

Explanation:

1. $arr is the array containing the elements.
2. array_reduce($arr, function($carry, $item) { return ($item > $carry) ? $item : $carry; }) reduces the array to the largest element using a callback function.

Using array_map() and array_combine() Functions

The array_map() function applies a callback to the elements of the given arrays. The array_combine() function creates an array by using one array for keys and another for its values. By using these functions, we can achieve the task in a unique way.

Example: This example shows the use of the above-mentioned approach.

<?php

$arr = [10, 20, 30, 40, 50];

$keys = array_keys($arr);
$values = array_values($arr);

$combined = array_combine($keys, $values);
$largest = max(array_map(function($key) use ($combined) {
    return $combined[$key];
}, array_keys($combined)));

echo "The Largest Element is: " . $largest;

?>

The Largest Element is: 50

Explanation:

• $arr is the array containing the elements.
• array_keys($arr) retrieves the keys of the array.
• array_values($arr) retrieves the values of the array.
• array_combine($keys, $values) combines the keys and values into a new associative array.
• array_map() applies a callback to the keys, retrieving the corresponding values from the combined array.
• max() finds the largest value from the resulting array.