DFA — binary, divisible by 3

Exactly one move per state and symbol, so a run is a single path. The string is accepted if that path ends in an accepting state.

Also written DFSM, deterministic finite state machine in the question papers.

Q

{r0, r1, r2}

Σ

{0, 1}

q₀

r0

F

{r0}

|δ|

6 transitions

• One state is current at a time; it is outlined in blue.
• The transition just taken is drawn in blue, and the symbol just read is boxed.
• If a state has no move on the next symbol, the run dies there and the string is rejected — that is the implicit dead state a textbook diagram leaves off.