<?php

/*
    script
*/

$a = random_array();
$b = array_process($a);

print_array($a, 'Array A');
print_array($b, 'Array B');


/*
    functions
*/

function array_process($arr) {
    $result = [];

    foreach ($arr as $val) {
        if (is_numeric($val) && $val % 2 == 0)
            $result[] = $val;
    }

    return $result;
}

function random_array() {
    $result = [];

    for ($i = 0; $i < rand(10, 20); $i++) {
        $result[] = rand(0, 999);
    }

    return $result;
}

function print_array($arr, $title = 'Array') {
    printf('<h3>%s</h3>', $title);
    echo '<table border=1>';
    echo '<tr><th>index</th><th>value</th><th>parity</th></tr>';

    foreach ($arr as $idx => $val) {
        printf('<tr><td>%d</td><td>%d</td><td>%s</td></tr>', $idx, $val, $val %2 == 0 ? 'even' : 'odd');
    }

    echo '</table>';
}