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

namespace OPG1
{
    //ФАСАД
    public class Facade
    {
        protected Subsystem1 _subsystem1;

        protected Subsystem2 _subsystem2;

        public Facade(Subsystem1 subsystem1, Subsystem2 subsystem2)
        {
            this._subsystem1 = subsystem1;
            this._subsystem2 = subsystem2;
        }

        public string Operation()
        {
            // типа сложная функциональность
            string result = "Арифметические процессы\n";
            result += "1 число:\n";
           
            result += this._subsystem2.operationX();
            result += "\n";
            result += "2 число:\n";

            result += this._subsystem2.operationY();
            result += "\n";
            result += this._subsystem1.operationN();
            result += this._subsystem2.operationYX();
            result += "\n";
            result += this._subsystem1.operation1();
            result += this._subsystem2.operationXY();
            return result;
        }
       

    }
    public class Subsystem1
    {
        public string operation1()
        {
            return "Добавление\n";
        }

        public string operationN()
        {
            return "Вычитание\n";
        }
    }
   
    public class Subsystem2
    {
        double x = 10;
        double y = 20;
        public double operationX()
        {
            
            return x;
        }

        public double operationY()
        {
            
            return y;
        }

        public double operationXY()
        {
            return x + y;
        }
        public double operationYX()
        {
            return x - y;
        }
    }

 
    class Client
    {
     //легкий интерфейс   
        public static void ClientCode(Facade facade)
        {
            Console.Write(facade.Operation());
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            
            Subsystem1 subsystem1 = new Subsystem1();
            Subsystem2 subsystem2 = new Subsystem2();
            Facade facade = new Facade(subsystem1, subsystem2);
            Client.ClientCode(facade);
            Console.ReadLine();
        }
    }
}