Need a little help with this code (force login)

i have this code that force id post to login.

function my_force_login() {
global $post;

if (!is_single()) return;

$ids = array(188, 185, 171); // array of post IDs that force login to read

if (in_array((int)$post->ID, $ids) && !is_user_logged_in()) {
auth_redirect();
}
}

how i can i change this instead of 188,185,171 – to all ids that i have in my site? or all posts from category?