title: How can I make it jump to the URL without www when it contains it?
body: <p>I'm trying to make <code>.htaccess</code>
  On this, I would like to state something in order to make visitor jump to the URL without www when it contains it as sub-domain.</p>
  
  <p>How can I write?
  For example, when a user goes to the page <a href="http://www.test-sample.com/sign_up" rel="nofollow">http://www.test-sample.com/sign_up</a>, I want it to redirect to <a href="http://test-sample.com/sign_up" rel="nofollow">http://test-sample.com/sign_up</a>
  but only when it contains www in sub-domain.
  Because there is rare case such as <a href="http://forum.test-sample.com/1443" rel="nofollow">http://forum.test-sample.com/1443</a></p>