Regex for string containing one string, but not another
<p>Have regex in our project that matches any url that contains the string 
"/pdf/":</p>

<pre><code>(.+)/pdf/.+
</code></pre>

<p>Need to modify it so that it won't match urls that also contain "help"</p>

<p>Example:</p>

<p>Shouldn't match: "/dealer/help/us/en/pdf/simple.pdf"
Should match: "/dealer/us/en/pdf/simple.pdf"</p>