regex - URL extension redirect help

I have a couple开发者_开发知识库 of domain extensions that I'd like to redirect to specific pages. Like example.de has to redirect to example.de/de/ and example.fr to example.fr/fr/.

How can I achieve this? I'm new to regex.

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You will edit your .htacess file and put something like to :

RedirectMatch permanent example\.de/$ http://example.de/de
RedirectMatch permanent example\.fr/$ http://example.fr/fr
....