$a = [
3,
4,
2,
8,
1,
9
];
$count = count($a)-2;
for($count;$count>0;$count--){
for($i=0;$i<=$count;$i++){
if($a[$i]>$a[$i+1]){
//change position
$j = $a[$i];
$a[$i] = $a[$i+1];
$a[$i+1] = $j;
}
}
}
function sort22($arr){
$left = [];
$right = [];
$mid = array_shift($arr);
$count = count($arr);
for($i=0;$i<$count;$i++){
if($arr[$i]<=$mid){
$left[] = $arr[$i];
}else{
$right[] = $arr[$i];
}
}
if(count($left)>1){
$left = sort22($left);
}
if(count($right)>1){
$right = sort22($right);
}
return array_merge($left,[$mid],$right);
}