htaccess given rewriterule non-www to www with subfolder and no filename

In various stack posts, I found the semi-solution to my problem. Just as the askers of those questions I wanted to be able to redirect non-www users to www. This should be able for subfolders as well.

It is when I use a link such as http://ift.tt/2l5b4O4 but it when I use http://ift.tt/1FgkCLL it will redirect me to http://example.com.

The code I found on stack:

# Redirect to www
RewriteCond %{HTTP_HOST} !^www\.
RewriteCond %{HTTPS}s on(s)|offs()
RewriteRule ^ http%1://www.%{HTTP_HOST}%{REQUEST_URI} [NE,L,R]