static void Main(string[] args)
{
ObjectStructure list = new ObjectStructure();
list.AddEmployee(new FulltimeEmployee("Mike", 2000));
list.AddEmployee(new FulltimeEmployee("Tony", 3000));
list.AddEmployee(new ParttimeEmployee("Nancen", 800));
list.AddEmployee(new ParttimeEmployee("Bibo", 500));
FinanceVisitor fVisitor = new FinanceVisitor();
HrVisitor hVisitor = new HrVisitor();
list.Accept(fVisitor);
list.Accept(hVisitor);
Console.ReadKey();
}