Function for sum weekends between two dates

SumWeekends.php

<?php
function sumWeekends($start, $end) {
  $start_date = strtotime($start);
	$end_date = strtotime($end);
	
	$n = floor(($end_date - $start_date) / 86400);
	$n_weekends = ceil($n/7);

	if (date("N", $start_date) == 6 && $n%7 == 0 ){
		$n_weekends++;
	}

	return $n_weekends;
}
?>