Possible Updates
Consider again the following state machine:
The possibleUpdates function is given as follows:
possibleUpdates(a, 0) = { (a, 0) }
possibleUpdates(a, 1) = { (b, 1) }
possibleUpdates(b, 0) = { (a, 0), (b, 1) }
possibleUpdates(b, 1) = { (b, 1) }
The third of these is the source of nondeterminism in this model. There are two possible updates when the state is b and the input is 0.