454  12.  - 

         operator (). 
     operator () -. -
,   trip_announcement  operator ()  .

bool trip_announcement::operator()(void)
{

list<trip_announcement>::iterator I;

if(directTrip())(
return(true) ;

}

I = UniverseOfDiscourse.begin();

if(validTrip(I,Origin)){
return(true) ;

}

return(false) ;

}

     ,      -
     . , ,  
     ,     
 :

 - 
 - 

   trip_announcement ""  ,    -
       ,   ,
        :

 - 

  trip_announcement  ,   -
     .   ,   
.        .  -
  .

if(directTrip()){

return(true) ;

}

I = UniverseOfDiscourse.begin();

if(validTrip(I,Origin)){

return(true) ;

}

""     operator () 
trip_anouncement.  directTrip ()  ,    
        -
 :

 - 

 validTrip (),  ,    ,  -
   (Depth First Search DFS).  
validTrip ()  directTrip ()    12.7.