implementing dfa for a binary string with at least two 0's after every 1

[lubabah]

i want to implement dfa that accepts the binary string with at least two 0's after every 1 .....

please help me ...

[weaknessforcats]

Are you going to do this in C or C++?

If you are using C++, you use the State design pattern to implement your finite state automaton.

Read this: http://bytes.com/topic/c/insights/66...patterns-state

There is an example.

If you are using C, then replace the polymorphism with a switch statement where the cases are the states.

[lubabah]

thank you........this is my code using C++.I did it very simple.

but it didn't say either it is accepted or rejected :/

#include <stdio.h>
#include <conio.h>
#include <iostream>
 
using namespace std;
int main ()
 
{
    int state = 0;
    char ch;
    while(1)
    {
        cin.get(ch);
            if (state == 0)
            {
                      if (ch == '0')
                      state = 0;
                      else
                      state = 1;
            }
 
            else if (state == 1)
            {
                      if (ch == '0')
                      state = 2;
                      else 
                      state = 4;
            }
 
            else if (state == 2)
            {
                      if (ch == '0')
                      state = 3;
                      else
                      state = 4;
            }
 
            else if (state == 3)
            {
                      if (ch == '0')
                      state = 3;
                      else 
                      state = 1;
            }
 
            else if (state == 4)
            {
                      if (ch = '0')
                      state = 4;
                      else
                      state = 4;
            }
 
    }
    if (state == 3 || state == 0)
    cout << "ACCEPTED :-)" <<endl ;
    else 
    cout << "REJECTED :-(" <<endl;   
 
   /* if (state == 3)
 
     cout << "ACCEPTED :-)" <<endl; 
    else if (state == 0)
     cout << "ACCEPTED :-)" <<endl; 
     else 
     cout << "REJECTED :-(" <<endl; */
 
     getch();
     return 0;
}

[donbock]

The while loop never ends, so your program doesn't fall through to that little bit at the end that decides whether or not to print ACCEPTED or REJECTED.
(If you used CODE tags then I could refer to specific line numbers.)