title: preg_match to domain.tld
body: <p>How can i get the strings that only contains domain.tld?</p>
  
  <pre><code>if (preg_match('^(?:[-A-Za-z0-9]+\.)+[A-Za-z]{2,6}$', $domain))
  echo "domain.tld found!";
  </code></pre>
  
  <p>but for the regex <code>^(?:[-A-Za-z0-9]+\.)+[A-Za-z]{2,6}$</code>, sub domains are also okay. But i just want to check "domain.tld". What regex should i use for it?</p>
  
  <p>Thank you.</p>