public override void Visit(PartTimeEmployee employee)
 {
     Console.WriteLine($"临时员工 {employee.Name} 实际工作时间为:{employee.WorkTime} 小时");
 }
 public abstract void Visit(PartTimeEmployee employee);
 public override void Visit(PartTimeEmployee employee)
 {
     Console.WriteLine($"临时员工 {employee.Name} 实际工资为:{employee.WorkTime * employee.HourWage} 元");
 }