combination regex and php still not work

hey all.i'm newbie at this problem.i have this data in table result:

item              range_code                   class
red               123x0001-123x0500             A
blue              123x0021-123x0100             //if null read zero
green             123x0001-123x0300             b

i want the result like:

item             qty           S           A         B          C
 red             500           0           1         0          0
 blue            80            0           0         0          0
 green           300           0           0         1          0

i have tried this code but still not work:

$sql= 'SELECT item, range_code as qty, class FROM result GROUP BY item, qty';
$result=mysql_query($sql);
while ($row=mysql_fetch_assoc($result)){
         preg_match_all('/\d+(?=-|$)/g',$row['qty'],$matches);
         echo intval($matches[0][1])-intval($matches[0][0])+1;
         开发者_如何学编程}

i still confuse for this problem. please help..

Not sure if this is doing what you want... if not, clarify if there are any edge cases that don't match, but based on your examples this should work.

<?php

$code = "123x0001-123x0500";
preg_match("/^\d+x(\d+)-\d+x(\d+)$/", $code, $matches);
echo intval($matches[2]) - intval($matches[1]) + 1;

?>

OUTPUT:

500

.

<?php

$codes = array("123x0001-123x0500",  "123x0021-123x0100", "123x0001-123x0300");

function getDiff($range) {
    preg_match("/^\d+x(\d+)-\d+x(\d+)$/", $range, $matches);
    return intval($matches[2]) - intval($matches[1]) + 1;
}

foreach ($codes as $code) {
    echo getDiff($code) . "\n";
}

?>

OUTPUT

500
80
300

Not sure how the S, A, B, C values are supposed to be computed. Perhaps you can elaborate on that.