date_default_timezone_set("Asia/Calcutta");
function dt_differ($start,$end){
$start = date("G:i:s:m:d:Y",strtotime($start));
$date1=explode(":",$start);
$end = date("G:i:s:m:d:Y",strtotime($end));
$date2=explode(":",$end);
$starttime = mktime(date($date1[0]),date($date1[1]),date($date1[2]),date($date1[3]),date($date1[4]),date($date1[5]));
$endtime = mktime(date($date2[0]),date($date2[1]),date($date2[2]),date($date2[3]),date($date2[4]),date($date2[5]));
$seconds_dif = $starttime-$endtime;
return $seconds_dif;
}