Library(int authors)
 {
     nAuthors = authors;
     storage  = StorageFactory.Instance.CreateStorage();
     storage.Open("library.dbs");
     db = new AssocDB(storage);
 }
 Hospital()
 {
     storage = StorageFactory.Instance.CreateStorage();
     storage.Open("hospital.dbs");
     db = new AssocDB(storage);
 }