Calculates the overlapping sums of a range of numbers (used for dates in a project)

dateFinder

#!/bin/php
<?php
function test($array) {
        $start = 0;
        $end = 0;
        $total = 0;
        foreach( $array as $index => $time) {
                if($start == 0 AND $end == 0) {
                        $start = $time['start'];
                        $end = $time['end'];
                }   
                elseif($time['start'] > $start AND $time['start'] < $end AND $time['end'] > $end) {
                        $end = $time['end'];
                }   
                elseif($time['start'] > $end) {
                        $total += ($end - $start);
                        $start = $time['start'];
                        $end = $time['end'];
                }   
                if($index == count($array) - 1) {
                        $total += ($end - $start);
                }   
        }   
        return $total;
}

$times = array();
array_push($times,array('start' => 1, 'end' => 5));
array_push($times,array('start' => 3, 'end' => 8));
array_push($times,array('start' => 6, 'end' => 7));
array_push($times,array('start' => 12, 'end' => 14));

print test($times);
?>