PHP Sort-quick sort-bubble sort-sort order

Quick Sort

$arr = Array (32,31,56,4,234,46,466,86,5);

function Kuaisu ($arr) {
if (!is_array ($arr) | | empty ($ARR)) {
return Array ();
}
Gets the length of the array
$len = count ($arr);

If there is only one element in the array, return the array directly
if ($len <= 1) {
return $arr;
}
$key [0] = $arr [0];
$left = Array ();
$right = Array ();

for ($i =1; $i < $len; $i + +) {
if ($arr [$i]<= $key [0]) {
$left []= $arr [$i];
}
else {
$right [] = $arr [$i];
}
}

/* Print_r ($left);
echo "<br>";
echo $key [0];
echo "<br>";
Print_r ($right);
echo "----------------*/

$left = Kuaisu ($left);
echo "$right = Kuaisu ($right);
/*
Print_r ($left);
echo "<br>";
echo $key [0];
echo "<br>";
Print_r ($right);
echo "*/
Return Array_merge ($left, $key, $right);
}
Print_r ($arr);
echo "<br>";
echo "

Print_r (Kuaisu ($arr));

Bubble sort

$arr = Array (0,1,2,3,4,5,6,7,8,9);

$len = count ($arr)-1; Optimization

for ($i = 0; $i < $len; $i + +) {

for ($j = 0; $j < $len-$i; $j + +) {

if ($arr [$j] < $arr [$j +1]) {

$tmp = $arr [$j +1];

$arr [$j +1] = $arr [$j];

$arr [$j] = $tmp;

}

}

}

Print_r ($arr);

Sequential sorting

function Shunxu ($arr) {
$count = count ($arr);
for ($i =0; $i < $count-1; $i + +) {
$p = $i;
for ($j = $i +1; $j < $count; $j + +) {
$p = $arr [$p] < $arr [$j]? $j: $p;
}
if ($p! = $i) {
$tmp = $arr [$i];
$arr [$i] = $arr [$p];
$arr [$p] = $tmp;
}
}
return $arr;

}
Print_r (Shunxu ($arr));

PHP Sort-quick sort-bubble sort-sort order