Redirect index example for codeigniter

redirect_index_example.php

class IndexController extends CI_Controller {
    function __construct() {
        parent::__construct();
        $this->load->helper('captcha');
        $this->load->model('user', 'user');
    }
    public function location($location_id) {
        $this->index($location_id);
    }
    public function index($location_id = 1) {
        $this->load->model('location', 'location');
        ...
    }
}