PHP replace string with ****@mail.com : <p>how can convert ?</p>

<p>Is there a quick and easy way to replace every letter of a word with an ****@mail.com</p>

<p>For example</p>

<pre><code>$mail = 'stack@mail.com';
echo $mail;
output -&gt; s****@mail.com
</code></pre>

<p>Thanks for answer me.</p>
