// cloning
 private MultiplexerProblem(MultiplexerProblem original, Cloner cloner)
     : base(original, cloner)
 {
     RegisterEventHandlers();
 }
 // cloning 
 private MultiplexerProblem(MultiplexerProblem original, Cloner cloner)
   : base(original, cloner) {
   RegisterEventHandlers();
 }