DFSA

DFSA stands for deterministic finite state automaton and is a mathematical model of computation used to design sequential of states logic circuits, which given any input string, x, accepts or rejects x. 

- a machine has a finite set of states, including a designated initial or start state and a designated set of accepting states.

- the machine is in only one state at a time; the state at any given time is called the current state. changing states from one state to another is called a transition.

- the machine stops when it has processed the entire input string in a manner of one symbol at a time.

- when it stops, if the current state is in an accepting state, it accepts the input of a string; otherwise, it rejects the input.