htaccess : how to redirect subfolder to the root subdomain?

So, I have the following URLs structure:

http://demo.mysite.com/subfolder1/
http://demo.mysite.com/subfolder2/
http://demo.mysite.com/subfolder3/
http://demo.mysite.com/subfolder3/file.ext
and so on............

Code (markup):

I want to redirect all traffic from the subfolders along with all files inside it to the root subdomain :

http://demo.mysite.com/subfolder1/   ->    http://demo.mysite.com/
http://demo.mysite.com/subfolder2/   ->    http://demo.mysite.com/
http://demo.mysite.com/subfolder3/   ->    http://demo.mysite.com/
http://demo.mysite.com/subfolder3/file.ext   ->    http://demo.mysite.com/

Code (markup):

What htaccess code should i put on my demo.mysite.com directory ??


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