<?php
$a = array(4,1,3,2,5);
$q = count($a);
for ($i = 0; $i < $q; $i++){
	for ($j = 0; $j < ($q-1); $j++){
		$J = $a[$j];
		if ($a[$j]>$a[$j+1]){
			$a[$j] = $a[$j+1];
			$a[$j+1] = $J;
		}
	}
}
print_r($a);