Wordpress URL rewriting

add_action('init', 'minsol_add_rewrite_rules');
function minsol_add_rewrite_rules() {
    add_rewrite_tag('%parameter%', '([^&]+)');
    add_rewrite_rule('^vis-side/([0-9]{1,})/', 
                     'index.php?p=<vis-side-id>&meter=$matches[1]');
}

'index.php?p=<vis-side-id>&meter=$matches[1]');

'index.php?p=<vis-side-id>&parameter=$matches[1]');

var_dump($wp_query->rules);

var_dump($wp_rewrite->rules);

add_rewrite_rule('^vis-side/([0-9]{1,})/', 
                 'index.php?p=152&center=$matches[1]');

add_rewrite_rule('vis-side/([0-9]{1,})/?', 
                 'index.php?p=152&center=$matches[1]',
                 'top');

var_dump($wp_rewrite->rules);

foreach ($wp_rewrite->rules as $regex => $route) {
    echo $regex . " => " . htmlentities($route) . "<br/>";
}