I am a beginner in Codeigniter and I saw a CI tutorial and was just trying to do a simple thing. I downloaded the CI and added this file to controller directory, but it won't work.

<?php

class site extends CI_Controller
{
    public function index()
    {
        echo "Hello World";
    }

    function dosomething()
    {
        echo "Do Something";
    }   
}    
?>

When I try to access it using http://..../index.php/site I get the output ... "no input file specified" .... by the way, I named the file site.php