I edited sudoers and saved it with a parsing error. (I tried to use visudo to edit the sudoers file but couldn't get the right command.)
Anyway, I now do not have a valid sudoers file, so I cannot use sudo. I need sudo to edit the sudoers file in /etc
I try to login as su but it doesn't accept the password I use for sudo. I have never set a password for su. I guess it must be the default. What is the default password for su ?