function example($key) {
$secret = 12345;
//$key = "Ключ";
$salt = "рыба";
$hash = md5( $secret.$key.$salt );
if($hash === "d829552aee0172179eb9fd1e5f1eefe0") {
echo $secret;
} else {
echo rand(13421234124,56567231231243245);
}
}
example("Ключ");