Write a PHP program to find out the maximum element between the first or last element in a given array of integers

<?php
function test($nums)
 { 
            $max = max($nums);

            return [$max, $max, $max, $max];
    
 }   

$a = [10, 20, -30, -40];

echo "Original array: " . implode(',', $a) . "\n";

$result = test($a);

echo "New array with maximum values: " . implode(',', $result);