PHP String Parsing

I have string wh开发者_如何学Goich contains something about "amount 3 val 6, amount 7 val 8" and so, what regular expression should I use to get array with corresponding amounts and values?

$str = "amount 3 val 6, amount 7 val 8";
preg_match_all('~amount (\d+) val (\d+)~i', $str, $matches);

echo '<pre>';
print_r($matches);
echo '</pre>';

$str = 'amount 3 val 6, amount 7 val 8';
preg_match_all('#amount\s+(\d+)\s+val\s+(\d+)#', $str, $matches);

All amounts in $matches[1], all vals in $matches[2].

amount\s*(\d*)\s*val\s*(\d*)

You can do the rest