ArraysInPHP - //Problem 4. Selection Sort

//Problem 4.    Selection Sort
//Sorting an array means to arrange its elements in increasing order. Write a script to sort an array. Use the "selection sort" //algorithm: Find the smallest element, move it at the first position, find the smallest from the rest, move it at the second position, //etc.
//Hint: Use a second array
<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <title></title>
    </head>
    <body>
        <form action="SelectionSort.php" method="post">
        <input type="text" name="text">
        <input type="submit" value="enter!">
        </form>
    </body>
</html>

<?php

function selectionSort(array $arr) {
    for ($i = 0; $i < count($arr); $i++) {
        $min = null;
        $minKey = null;
        for($j = $i; $j < count($arr); $j++) {
            if (null === $min || $arr[$j] < $min) {
                $minKey = $j;
                $min = $arr[$j];
            }
        }
        $arr[$minKey] = $arr[$i];
        $arr[$i] = $min;
    }
    return $arr;
}
$myString = $_POST['text'];
$myArray=explode(" ", $myString);
$sortedArr = selectionSort($myArray);
echo '<pre>' . print_r($sortedArr, true) . '</pre>';
?>