helper.php

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

function active($name, $number)
{
    $ci = get_instance();

    if($name == 'home' && $ci->uri->segment(2) == "" && $number == 1)
    {
        return "class='active'";
    }
    elseif($name=="about" && $ci->uri->segment(2) == "about" && $number == 2)
    {
        return "class='active'";
    }
    elseif($name=="story" && $number == 3)
    {
        return "class='active'";
    }
}