How do I remove specific URL from user input?
<p>I want remove some URL from user input.</p>

<p>Example user input</p>

<pre><code>$input = 'http://www.yahoo.com/';
$input = 'http://yahoo.com/';
$input = 'www.yahoo.com';
$input = 'yahoo.com';
$input = 'http://answers.yahoo.com/question/index;_ylt=AhiI2Ax0jmujpU01wK7W4cLj1KIX;_ylv=3?qid=20110224130854AA9LGdy';
$input = '&lt;a href="http://yahoo.com"&gt;yahoo&lt;/a&gt;';
$input = '&lt;a href="http://yahoo.com"&gt;http://yahoo.com&lt;/a&gt;';
$input = 'I love &lt;a href="http://yahoo.com"&gt;http://yahoo.com&lt;/a&gt;';

output I love
</code></pre>

<p>Any domain with <code>yahoo.com</code> I want remove the output or return empty result. Maybe more than one domain. Let me know.</p>
