Online PHP editor | output for 2WoUp

@ 2015-10-11T12:25:01Z

<?php
function datediffInWeeks($date1, $date2)
{
    if($date1 > $date2) return datediffInWeeks($date2, $date1);
    $first = DateTime::createFromFormat('m/d/Y', $date1);
    $second = DateTime::createFromFormat('m/d/Y', $date2)->addDays(1);
    return floor($first->diff($second)->days/7);
}

var_dump(datediffInWeeks('1/1/2013', '1/7/2013'));// 21
var_dump(datediffInWeeks('6/4/2013', '1/2/2013'));// 21

Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6: Fatal error: Uncaught Error: Call to undefined method DateTime::addDays() in /in/2WoUp:6 Stack trace: #0 /in/2WoUp(10): datediffInWeeks('1/1/2013', '1/7/2013') #1 {main} thrown in /in/2WoUp on line 6
Process exited with code 255.
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40: Fatal error: Call to undefined method DateTime::addDays() in /in/2WoUp on line 6
Process exited with code 255.

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