void IDictionary <PassengerClassType, PassengerClass> .Add(PassengerClassType key, PassengerClass value) { ClassDemand.Add(key, value); }
void ICollection <KeyValuePair <PassengerClassType, PassengerClass> > .Add(KeyValuePair <PassengerClassType, PassengerClass> item) { ClassDemand.Add(item.Key, item.Value); }