using System;

public interface IPerson

{

    string Name { get; set; }

    int Age { get; set; }

    bool IsOlderThan50();

}

​

public interface IEmployee

{

    double TotalSalary { get; set; }

    bool IsOlderThan50();

}

​

public class Employee : IEmployee, IPerson

{

    //Implement Person's property

    public string Name { get; set; }

    private int _age;

    public int Age

    {

        get

        {

            return _age;

        }

        set

        {

            if (value > 0)

                _age = value;

        }

    }

​

    //Implement Employee's property

    public double TotalSalary { get; set; }

​

    // constructor

    public Employee()

    {

    }

​

    //Implement Person's Function

    public bool IsOlderThan50()

    {

        return Age > 50;

    }

​

    //Implement Employee's Function

    public double CalculateMonthlySalary()

    {

        return TotalSalary / 12;

    }

}

​

public class Program

{

    public static void Main()

    {

        Employee e1 = new Employee();

        e1.Name = "John";

        e1.Age = 19;

        e1.TotalSalary = 36000;

​

        Console.WriteLine("Is {0} older than 50? {1}", e1.Name, e1.IsOlderThan50());

        Console.WriteLine("{0}'s month salary equals to {1}", e1.Name, e1.CalculateMonthlySalary());

    }

}