Published on 03 Dec 2013 | over 3 years ago
Deterministic Finite Automata or DFA construction method is described in this tutorial with an example.
A deterministic finite state automaton (DFA) is a simple language recognition device. It can be seen as a machine working to give an indication about strings which are given in input or it can be given a mathematical definition.
Strings are fed into the device by means of an input tape, which is divided into squares, each one holding one symbol. The main part of the machine itself is a black box which is, at any specified moment, in one of a finite number of distinct internal states, among which we distinguish an initial state and some final states. This black box, called the finite control, can sense what symbol is written at any position of the input tape by means of a movable reading head. Initially, the reading head is placed at the leftmost square of the tape and the finite control is set in a designated initial state.