Such profound knowledge~ Sorting can be achieved using only two stacks

$stackA = range(1,9);
shuffle($stackA);
print_r($stackA);
$stackB = array();
while(count($stackA)){
    $tmpA = array_shift($stackA);
    while(count($stackB)){
        $tmpB = array_shift($stackB);
        if($tmpB>=$tmpA){
            array_unshift($stackB,$tmpB);
            break;
        }else{
            array_unshift($stackA,$tmpB);
        }
    }
    array_unshift($stackB,$tmpA);
}
print_r($stackB);

Yeah, LZ has been thinking about it for five years and finally realized it today hahahaha~

The above has introduced a lot of profound knowledge~ Sorting can be achieved using only two stacks, including all aspects of it. I hope it will be helpful to friends who are interested in PHP tutorials.