<?php
$datetime1 = new DateTime('2009-10-11');
$datetime2 = new DateTime('2009-10-23');
$interval = $datetime1->diff($datetime2);
echo $interval->days;
PD9waHAKCiRkYXRldGltZTEgPSBuZXcgRGF0ZVRpbWUoJzIwMDktMTAtMTEnKTsKJGRhdGV0aW1lMiA9IG5ldyBEYXRlVGltZSgnMjAwOS0xMC0yMycpOwokaW50ZXJ2YWwgPSAkZGF0ZXRpbWUxLT5kaWZmKCRkYXRldGltZTIpOwplY2hvICRpbnRlcnZhbC0+ZGF5czs=