PHP &amp; Date

PHP & Date

Hi there,

I'm having trouble trying to do something similar to the website www.foxrentacar.com on the part to calculate the rates...

This is the code:
<?

if (($dropoff_array[day] - $pickup_array[day]) == 0) {

$days = 1;

} else {

$days = ($dropoff_array[day] - $pickup_array[day]);

}

$total = $days * $pickup_array[car];

echo $total;

But when I select the pickup date like May 29 and the dropoff date like June 04 it returns a invalid result...

I hope somebody can help me.

Thanks.