string name[30];  // The name list on line 1
  map a;            // Assignment


 Initialization:

   for ( int i = 0; i < N; i++ )
   {
      cin >> n;
      name[i] = n;
      a[n] = "";
   }

 Example:

  name[ ] = "Ada"   "Alan"   "Grace"   "John"

  a["Ada"] = "", a["Alan"] = "", a["Grace"] = "", a["John"] = ""
  

 Example:

  name[ ] = "Ada"   "Alan"   "Grace"   "John"

  a["Ada"] = "", a["Alan"] = "", a["Grace"] = "", a["John"] = ""


   // Read and process line 2
   for ( int i = 0; i < N; i++ )
   {
      src = name[i];      // This was the name opposite to the input
      cin >> dest;

      // Has src been assigned/mapped ?
      if ( a[src] == "" )
         a[src] = dest;         // No, now src is mapped

      // Check for self-mapped violations
      if ( src == dest )
      {
         cout << "bad" << endl;
         exit(0);
      }

      // Check for a  <--> b  violations
      if ( a[dest] != "" )       // dest is already assigned
      {
         if ( a[dest] != src )  // Then dest MUST be assigned to src
         {
            cout << "bad" << endl;
            exit(0);
         }
      }
   }