$string1="CA" . "Los Angeles" . "1440x900" . "en-us" . "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)" . "";

$string2="CA" . "Los Angeles" . "1280x1024" . "en-us" . "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.0.04506)" . "";