Online PHP editor | output for J8I6r

<?php $time1 = new DateTime('2018-10-01 13:00:00'); $time2 = new DateTime('2018-10-01 13:59:00'); $time3 = new DateTime('2018-10-01 14:29:00'); $time4 = new DateTime('2018-10-01 15:29:00'); $part1= date_diff($time2,$time1)->format('%h:%i:%s'); $part2= date_diff($time3,$time2)->format('%h:%i:%s'); $part3= date_diff($time4,$time3)->format('%h:%i:%s'); $part4 = (new DateTime('midnight')) ->add(date_diff($time2, $time1)) ->add(date_diff($time4,$time3)) ->diff(new DateTime('midnight')) ->format('%h:%i:%s'); echo $part4;