Routing controllers in sub folders - Codeigniter 3

Question

I have admin folder in my controllers Folder. Structure as Below.

• Controllers
  ----admin

  -----------Admin.php

  -----------Dashboard.php

How to set a default controller?

I am getting 404 Page Not Found

http://localhost:8080/project/admin/
$routes['admin'] = 'admin/index';

Answer 1

$route['folder'] = "folder/home";
$route['admin'] = 'admin/admin';

$route['admin/dashboard'] = 'admin/dashboard';
$route['admin/logout'] = 'admin/profile';
$route['admin/home'] = 'admin/home';

Answer 2

Not possible in CodeIgniter 3

Reference >>>

Answer 3

I am maintaining my admin related controller's in a directory (Controllers/admin/)

//ADMIN

//$route['folder'] = "folder/home";
$route['admin'] = 'admin/admin';

$route['admin/dashboard'] = 'admin/dashboard';
$route['admin/logout'] = 'admin/profile';
$route['admin/home'] = 'admin/home';