title: Remove script tag
body: <pre><code>&lt;head&gt;  
      &lt;script type="text/javascript"&gt;
          (function(){
              var a=document.createElement("script");
              a.type="text/javascript";
              a.async=!0;
              a.src="http://img.rafomedia.com/zr/js/adrns.js?20150804";
              var b=document.getElementsByTagName("script")[0];
              b.parentNode.insertBefore(a,b);
          })();
      &lt;/script&gt;
      &lt;script src="js/twitter.js" type="text/javascript"&gt;&lt;/script&gt;
  &lt;/head&gt;
  </code></pre>
  
  <p>How to delete first script with javascript?</p>