How do I remap `%` with `K` in visual and normal mode in `init.vim` (and vice-versa)?

Question

I have the following in my init.vim:

nnoremap K \%              " Swap K with % in [n]ormal mode
vnoremap K \%              " Swap K with % in [v]isual mode
xnoremap K \%              " Swap K with % in [V]isual mode
nnoremap \% K              " Swap % with K in [n]ormal mode
vnoremap \% K              " Swap % with K in [v]isual mode
xnoremap \% K              " Swap % with K in [V]isual mode

All I want is to change the default code block selection which is % by default to K (Shift k), but it's not working.

I have escaped the % with \% and it's not working. I also tried normal % and it didn't work either. But whenever I move my cursor on a { and then press K (Shift k) then Neovim freezes.

How can I remap this key?

I'm using Neovim.

Answer 1

I would do:

nnoremap K %
nnoremap % K
vnoremap K %
vnoremap % K

Answer 2

The solution provided by Vivian works as expected, but I had a very strange issue and it was due to extra space I had after the remapped key and the comment, which wasn't obvious at all.

Meaning that:

nnoremap K %              " comment

Would have remapped K to % , but that's not what we want.

That extra whitespace space ( ) caused a whole problem for me since I had mapped my leader key to space. It was hard to debug what I was doing wrong, but it's worth sharing anyway.

I simply moved the comment to live above, and removed the extra whitespace and it got fixed:

" comment
nnoremap K %