PHP DOMXPath query to return value - php

Question

I want to get and show the title, tel, fax and address if they exist.
HTML code could be like :
<div id="id1">
<div class="AB">
<ul>
<li class="title"> AGENCE X </li>
<li class="tel"> 060000000</li>
<li class="fax"> 06000000</li>
<li class="address> this is the address </li>
</ul>
</div>
<div class="AB"> //the same class name
<ul>
<li class="titre"> AGENCE X </li>
<li class="tel"> 060000000</li>
<li class="fax"> 06000000</li>
</ul>
</div>
<div>...</div>
</div>
I wrote this code but I didn't know how to write the condition "if a node with class name 'address' or 'fax' or 'tel' exist' then do X.
Here is my code:
$doc = new DOMDocument();
#$doc->loadHTMLFile('http://website.com');
$node = $doc->getElementsByTagName('div') ;
$xpath=new DOMXPath($doc);
$titre=$xpath->query('//div/ul/li[#class="titre"]');
$adresse=$xpath->query('//div/ul/li[#class="adresse"]');
$phone=$xpath->query('//div/ul/li[#class="phone"]');
$fax=$xpath->query('//div/ul/li[#class="fax"]');
$a=0;$b=0;$c=0;
for($i=0;$i<$titre->length;$i++)
{
echo $titre->item($i)->nodeValue.'<br/>' ;
if(a "li" has classe="adresse" existe)
{ for($a=0;$a<$adresse->length;$a++)
{
echo $adresse->item($a)->nodeValue.'<br/>' ;
$a++;
}
}
if(a "li" has classe="titre" existe){ for($b=0;$b<$phone->length;$b++)
{
echo $titre->item($b)->nodeValue.'<br/>' ;
$b++;
}
}
if(a "li" has classe="fax" existe) { for($c=0;$c<$fax->length;$c++)
{
echo $fax->item($c)->nodeValue.'<br/>' ;
$c++;
}
}
}
Could someone tell me how can I would write this condition or another solution?