Split a time range into pieces by other time ranges

Question

I have a complicated task that I have been beating my head against the wall now for a few days. I\'ve tried about 4 different approaches, however each seems to stall and it

Answer 1

The code should speak for itself:

$original_shift[0]['start'] = '14:30:00';
$original_shift[0]['end'] = '18:30:00';

$breaks[0]['start'] = '14:30:00';
$breaks[0]['end'] = '15:30:00';
$breaks[1]['start'] = '16:30:00';
$breaks[1]['end'] = '17:30:00';

$modified_shift = array(
    array('start' => $original_shift[0]['start'])
);

for($x = 0, $y = count($breaks), $z = 0; $x < $y; $x++){
    $modified_shift[$z]['end'] = $breaks[$x]['start'];
    if($modified_shift[$z]['end'] != $modified_shift[$z]['start']){
        $z++;       
    }
    $modified_shift[$z]['start'] = $breaks[$x]['end'];
}

$modified_shift[$z]['end'] = $original_shift[0]['end'];

if($modified_shift[$z]['end'] == $modified_shift[$z]['start']){
    unset($modified_shift[$z]);
}