I am trying to draw a Turing Machine diagram where I have a state and I go to one state if the current symbol pointed to by the head is an a or b, so I have (a, b) on that edge. I need another transition for when it's not a AND not b to go to another state. I don't want to label the edge as (!a, !b) as I think this makes my machine non-deterministic since technically a would be !b and could follow this transition, same with b and !a. I am not able to find common notation for something like this. All the examples I find show a single symbol transition of something like a and then !a, but not multiple symbols like my case. Thanks for any advice.