//Note: spaces added for < ... > for this html file to display correctly, 
//please delete the spaces after downloading this file, otherwise it 
//will not compile
//
#include "iostream.h"
#include < list>  //space added for html file, please remove the space
#include < map>
using namespace std ;
class Transition
{
public: 
    Transition ( int cs, int ie, int in) 
    { 
        m_iCurrentState = cs ;
        m_iEvent = ie;
        m_iNextState = in ;
    }
    int GetCurrentState ( ) const { return m_iCurrentState ; } 
    int GetEvent ( ) const { return m_iEvent ; } 
    int GetNextState ( ) const { return m_iNextState ; } 
private :
    
    int m_iCurrentState ; //this is subscript of map
    int m_iEvent ;
    int m_iNextState ;

} ;
void processingEvent ( int event ) 
{
    cout << "processingEvent: " << event << endl ;
}
int findNextState ( map < int, list < Transition > > &stateMap,  
                    int currentState, int eventReceived ) 
{
    int nextState = -1 ;
    list< Transition> tl = stateMap[currentState];
    list< Transition>::iterator it ;
    for ( it = tl.begin( ) ; it != tl.end( ) ; it++ ) 
    {
        if ( it->GetEvent( ) == eventReceived ) 
        {
            nextState = it->GetNextState( ) ;
            break ;
        }
    }  

    return nextState ;
}
int main ( void ) 
{

    list< Transition> l ;
    map< int, list< Transition> > m ;
    Transition t0 (0, 0, 1 ) ;
    Transition t1 (1, 1, 2 ) ;
    Transition t2 (2, 2, 0 ) ;
    Transition t3 (2, 3, 0 ) ;

    m[0].push_back ( t0 ) ; //calling list::push_back
    m[1].push_back ( t1 ) ;
    m[2].push_back ( t2 ) ;
    m[2].push_back ( t3 ) ;

    int event = 0 ;
    int goodState = 1 ;
    int currentState = 0 ;
    while ( goodState == 1 )
    {
        int nextState = findNextState ( m, currentState, event) ;
        if ( nextState == -1 ) 
        {
            goodState = 0 ;
        }
    
        cout << "currentState = " << currentState << endl ;
        processingEvent ( event ) ;
        cout << "nextState = " << nextState << endl ;
        cout << endl ;
        
        currentState = nextState ;
        event++ ;
    }
/*
Output:
currentState = 0
processingEvent: 0
nextState = 1

currentState = 1
processingEvent: 1
nextState = 2

currentState = 2
processingEvent: 2
nextState = 0

currentState = 0
processingEvent: 3
nextState = -1

*/
}