How to create foo.com/user in Zend?

$routes = array();
        $routes['entry']  = new Zend_Controller_Router_Route_Regex('SOME REGEX HERE',
            array(
                'controller' => 'profile',
                'action'     => 'show'
            ),
            array(
                'id' => "dsadsa", // maps first subpattern "(d+)" to "id" parameter
                1 => 'id' // maps first subpattern "(d+)" to "id" parameter
            )
        );

$router->addRoutes($routes);

$routes = array();

$routes['entry'] = new Zend_Controller_Router_Route(
    ':userName',
    array(
        'controller' => 'profile',
        'action'     => 'show'
    )
);