emacs c++ code completion help

[GMS S]

[
Here's another one,
http://www.emacswiki.org/emacs/AutoComplete
http://www.emacswiki.org/emacs/auto-complete.el

For more try this,
http://www.google.ca/search?q=autocomplete.el

HTH

-- 
Suvayu

Open source is the future. It sets us free.
]

I followed this.
http://www.emacswiki.org/emacs/AutoComplete#toc6
But can't manage to install it for c++ auto code completion.
Would you please tell how to install it for c++ auto code completion?

I put the auto-complete.el in /home/account/.emacs.d directory.

cat .emacs
(require 'auto-complete)
(global-auto-complete-mode t)

But it is not working for c++ code completion.
May be I missed to do some configuration.

And from demo
http://www.cx4a.org/pub/ac-demo/ac-demo.html

can't understand where to write 

requie 'auto complete
auto complete