WorkerClasss

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace abstractClass_06_06_2017
{
    class Program
    {
        interface IWorker
        {
            string Name { get; set; }
            string Surname { get; set; }
            void SetSalary(int a);
            void PaySalary();
        }
        interface IManager
        {
            int ManagerAdd { get; set; }
        }
        abstract class Worker : IWorker
        {
            private string _name;
            private string _surname;
            private int _salary;

            public string Name
            {
                get { return _name; }
                set { _name = value; }
            }
            public string Surname
            {
                get { return _surname; }
                set { _surname = value; }
            }
            public int Salary
            {
                get { return _salary; }
                set
                {
                    if (value > 0)
                        _salary = value;
                    else
                        _salary = 2000;
                }
            }

            public void SetSalary(int p = 2000) { Salary = p; }
            public virtual void PaySalary() { Console.Write("Salary to pay: " + Salary + " zł"); }

            protected Worker()
            {
                SetSalary();
            }
        }

        class Manager : Worker, IWorker, IManager
        {
            private int _managerAdd;
            private int _monthlyBonus;
            public int ManagerAdd
            {
                get { return _managerAdd; }
                set
                {
                    if (value > 0)
                        _managerAdd = value;
                    else
                        _managerAdd = 2000;
                }
            }
            public int MonthlyBonus
            {
                get { return _monthlyBonus; }
                set
                {
                    if (value > 0)
                        _monthlyBonus = value;
                    else
                        _monthlyBonus = 1000;
                }
            }
            public override void PaySalary()
            {
                Console.WriteLine("Salary to pay: " + (Salary + ManagerAdd + MonthlyBonus) + " zł");
            }
            public Manager()
            {
                ManagerAdd = 2000;
                MonthlyBonus = 1000;
            }

        }

        class Seller : Worker
        {
            private int _monthlyBonus;
            public int MonthlyBonus
            {
                get { return _monthlyBonus; }
                set
                {
                    if (value > 0)
                        _monthlyBonus = value;
                    else
                        _monthlyBonus = 500;
                }
            }
            public override void PaySalary()
            {
                base.PaySalary();
                Console.Write($" and additional {MonthlyBonus} zł monthly bonus");
            }
            public Seller()
            {
                MonthlyBonus = 500;
            }
        }

        static void Main(string[] args)
        {
            Manager manager = new Manager();
            manager.PaySalary();
            Seller seller = new Seller();
            seller.PaySalary();




            Console.ReadKey();
        }
    }
}