I'm failing at creating a script for my .htaccess file.

I want the following Rewrites:

* `www.domain.tld -> domain.tld` (no problem)
* `admin.domain.tld/(.*) -> domain.tld/?show=admin$1`
* `(everyothersubdomain).domain.tld -> domain.tld/?show=everyothersubdomain` (I created a wildcard subdomain for that)

Is anyone good at this? I failed after several tries with Error 500 or simply the indexpage without any get-parameters (index.php is just print\_r($\_GET)).

Thanks