Online PHP editor | output for JkNf2

@ 2014-08-28T08:06:08Z

<?php
$testArray = array(
    'sub1.sub2.example.co.uk',
    'sub1.example.com',
    'example.com',
    'sub1.sub2.sub3.example.co.uk',
    'sub1.sub2.sub3.example.com',
    'sub1.sub2.example.com'
);

foreach($testArray as $k => $v)
{
    echo $k." => ".extract_domain($v)."\n";
}

function extract_domain($domain)
{
    if(preg_match("/(?P<domain>[a-z0-9][a-z0-9\-]{1,63}\.[a-z\.]{2,6})$/i", $domain, $matches))
    {
        return $matches['domain'];
    } else {
        return $domain;
    }
}

function extract_subdomains($domain)
{
    $subdomains = $domain;
    $domain = extract_domain($subdomains);

    $subdomains = rtrim(strstr($subdomains, $domain, true), '.');

    return $subdomains;
}

Output for 4.3.3 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6: 0 => example.co.uk 1 => example.com 2 => example.com 3 => example.co.uk 4 => example.com 5 => example.com
Output for 4.3.0 - 4.3.2: Notice: Undefined index: domain in /in/JkNf2 on line 20 0 => Notice: Undefined index: domain in /in/JkNf2 on line 20 1 => Notice: Undefined index: domain in /in/JkNf2 on line 20 2 => Notice: Undefined index: domain in /in/JkNf2 on line 20 3 => Notice: Undefined index: domain in /in/JkNf2 on line 20 4 => Notice: Undefined index: domain in /in/JkNf2 on line 20 5 =>

preferences:dark modelive preview