How To Add Facebook Comment Code To Below Post

I want to add this code from facebook:

<div id="fb-root"></div>
<script>(function(d, s, id) {
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src = "//connect.facebook.net/en_US/sdk.js#xfbml=1&version=v2.4";
fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));</script>

I want it to show below the related articles. Where should I input this code.

or this code?

<div class="fb-comments" data-href="http://developers.facebook.com/docs/plugins/comments/" data-numposts="5"></div>

Facebook gave me 2 code but I don’t know which one to use and where to place it

Please advise

Hi,

add more information
http://ryanbradley.com/blog/how-to-install-facebook-comments-on-wordpress-site