Is fast (repeated) undo possible in emacs?

Question

I use emacs and I have a problem with it\'s undo.

(Sorry, maybe this is a stupid question, but I did not find anything about it in the internet, whilst it should be

Answer 1

Finally I found additional way of doing so: C-x u C-x z z z z z

But ctrl / is easier.

Many thanks to brbcoding