Codeigniter Profile Custom URL

Question

I am trying to create my own profile URL, for example site / u / username I found this How to make url / username in codeigniter?

but still it still shows 404. When I try to access the site / u / username

my routes.php

$route['default_controller'] = "guest";
$route['404_override'] = 'u';

my model

   function cekuser($username)
   {
    $query = $this->db->query("SELECT * FROM usertable WHERE username = '$username'");
        $query = $query->result_array();
        if($query){
            return $query[0];
        };
   }

my controller

<?php class U extends CI_Controller {
    public function __construct() {
            parent::__construct(); 
    }

    public function index()
    {
        $username = $this->uri->segment(1);

        if (empty($username)) {
            $this->show_404();
        }

        $this->load->model('m_login');

        // Check if parameter is not a valid username.
        if (!$this->m_login->cekuser($username)) {
            $this->displayPageNotFound();
        } else { 
            $this->load->view('template');
        }
    }

    protected function displayPageNotFound() {
        $this->output->set_status_header('404');
        $this->load->view('notfound');
    }
}

Answer 1

route.php

instead $route['404_override'] = 'u';

Add

$route['u/(:any)'] = 'u/showuserinfo';

In the controller

Add method

function showuserinfo($name)
{
 $this->load->model('m_login');
  if (empty($name))
  {
        $name = $this->uri->segment(2);
  }
  $user = $this->m_login->cekuser($name);
  if (!empty($user))
  {
        $this->load->view('template', $user);
  }
  else
  {
        echo 'User Not found';
  }
}

Answer 2

$route['404_override'] = 'controller name';

Add

$route['controller name/(:any)'] = 'controller name/any name';