========================================================================
TextualDFAs
Author: Bob Dondero
========================================================================

Note that:

-- A DFA consists of states and transitions.

-- Each transition is labeled with exactly one character or character
   set.

-- In a DFA the next state is a function of the current state and
   the current character. The next state is a function of *only* the 
   current state and the current character.

-- A DFA indicates which state is the start state.

-- A DFA indicates whether each state is an accepting state or a
   rejecting state.

------------------------------------------------------------------------
Textual representation of the "input contains an even number of zeros" 
DFA from the Wikipedia "Deterministic finite automaton" page.
------------------------------------------------------------------------

S1 (accept) <-- the start state
   0:  S2
   1:  S1
   
S2 (reject)
   0:  S1
   1:  S2
   
------------------------------------------------------------------------
Textual representation of the "input contains an even number of zeros" 
DFA from the Wikipedia "Deterministic finite automaton" page with
descriptive state names. Your Assignment 1 DFA should use descriptive
state names.
------------------------------------------------------------------------

EVEN_NUMBER_OF_ZEROS (accept) <-- the start state
   0:  ODD_NUMBER_OF_ZEROS
   1:  EVEN_NUMBER_OF_ZEROS
   
ODD_NUMBER_OF_ZEROS (reject)
   0:  EVEN_NUMBER_OF_ZEROS
   1:  ODD_NUMBER_OF_ZEROS

------------------------------------------------------------------------
Textual representation of the "Does the string have 'nano' in it"
DFA from the lecture appendix (and nano.pdf in this directory)
------------------------------------------------------------------------
   
START (reject) <-- the start state
   n:  N
   other:  START

N (reject)
   n:  N
   a:  NA
   other:  START
   
NA (reject)
   n:  NAN
   other:  START
   
NAN (reject)
   n:  N
   a:  NA
   o:  NANO
   other:  START
   
NANO (accept)
   other:  NANO