PHP 排序冒泡算法 经典面试题

<?php
$unsorted = array();

for ($i = 0; $i < 10; $i++) {
	$unsorted[] = rand(0,1000);
}

print "Unsorted Array. <br />";
print implode(',', $unsorted);

print "<br />";

print "Sorted Array. <br />";
$sort = bubble_sort($unsorted);
print implode(',',$sort);
 
function bubble_sort ($arr = array()) {	
	$size = false;	
	if ($arr and is_array($arr)) {
		$size = count($arr);				
		for ($i = 0; $i < $size; $i++) {			
			for ($j = 0; $j < $size - $i - 1; $j++) {																					
				if ($arr[$j+1] < $arr[$j]) {
					// switch two elements
					list($arr[$j], $arr[$j+1]) = array($arr[$j+1], $arr[$j]);  		
 			                // $temp = $arr[$j+1];
                                        // $arr[$j+1] = $arr[$j];
                                        // $arr[$j] = $temp;
				}							
			}						
		}		
	}		
	return $arr;
}