Trick to delete controller in query string

[eluser]Cahyono[/eluser]
I try to change http://localhost/index.php?c=welcome&m=home into http://localhost/index.php?m=home

So I want to delete c=welcome from URL so that shorter. After trial and error, I found like this:

in file system\application\config\routes.php :

Code:

$route['default_controller'] = "welcome";

in file system\Libraries\Router.php search on function _validate_request($segments):

Code:

// Can't find the requested controller...
show_404($segments[0]);

Add above so become this below:

Code:

$segments[0] = $this->default_controller;
return $segments;
// Can't find the requested controller...
show_404($segments[0]);

That's it. It's work fine to me.