title: How to set default controller inside n subfolder in codeigniter 3
body: <pre><code>-Myproject
    -application
      -controllers
       -subfolder1
          -subfolder2
              -subfolder3
                -subfolder(..n)
                   Controller.php
  </code></pre>
  
  <p>And need to set <code>routes.php</code></p>
  
  <pre><code>$route['default_controller'] = 'subfolder1/subfolder2/subfolder3/subfolder(..n)/controller';
  </code></pre>