using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Calculator
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void label1_Click(object sender, EventArgs e)
        {

        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void Multiplication_Click(object sender, EventArgs e)
        {
            //очищение памяти + не нажата ли кнопка??
        }

        private void Division_Click(object sender, EventArgs e)
        {

        }
    }

    public interface IInterfaceCalc
        {
            void Put_A(double a);               //запомнить a
            void Clear_A();                     //очистить память
            double Multiplication(double b);    //умножение
            double Division(double b);          //деление
            double Sum(double b);               //сумма
            double Subtraction(double b);       //вычитание
            double Square();                    //квадрат
            double Factorial();                 //факториал
            double MemoryShow();                //показать содержимое регистра памяти
            void Memory_Clear();                //стереть содержимое регистра
        }

    public class Calc : IInterfaceCalc
    {
        private double a = 0;
        private double memory = 0;

        public void Put_A(double a)
        {
            this.a = a;
        }

        public void Clear_A()
        {
            a = 0;
        }

        public double Multiplication(double b)
        {
            return a * b;
        }

        public double Division(double b)
        {
            return a / b;
        }

        public double Sum(double b)
        {
            return a + b;
        }

        public double Subtraction(double b)
        {
            return a - b;
        }

        public double Square()
        {
            return Math.Pow(a, 2.0);
        }

        public double Factorial()
        {
            double f = 1;
            for (int i = 1; i <= a; i++)
            {
                f *= (double)i;
            }
            return f;
        }

        public double MemoryShow()
        {
            return memory;
        }

        public void Memory_Clear()
        {
            memory = 0.0;
        }
    }


}