using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication1
{
    /// <summary>
    /// Абстрактный класс Операции.
    /// </summary>



    abstract class Operation
    {
        public abstract Double Calculate();

    }

    /// <summary>
    /// Абстрактный класс Унарной Операции. Наследуется от класса всех Операций
    /// </summary>
    abstract class UnaryOperation : Operation
    {
        protected Double Number;
        public UnaryOperation(Double number)
        {
            Number = number;
        }
    }
    /// <summary>
    /// Абстрактный класс Бинарной Опрерации. Наследуется от класса всех Операций.
    /// </summary>
    abstract class BinaryOperation : Operation
    {
        protected Double Number1;
        protected Double Number2;
        public BinaryOperation(Double number1, Double number2)
        {
            Number1 = number1;
            Number2 = number2;
        }
    }
    class SumOperation : BinaryOperation
    {
        public SumOperation(Double number1, Double number2)
            : base(number1, number2)
        { }
        public override Double Calculate()
        {
            return Number1 + Number2;
        }
    }
    class MinOperation : BinaryOperation
    {
        public MinOperation(Double number1, Double number2)
            : base(number1, number2)
        { }
        public override Double Calculate()
        {
            return Number1 - Number2;
        }
    }

    class Factorial : UnaryOperation
    {
        public Factorial(Double number)
            : base(number)
        { }
        public override Double Calculate()
        {
                Double Factorial = 1;
                for (int i = 1; i <= Number; i++)
                {
                    Factorial = Factorial * i;
                }

            return Factorial;

        }
    }

    class Calculator
    {
        public void StartWork()
        {
            List<Operation> operations = new List<Operation>();
            while (true)
            {
                Console.Write("Input expression = ");
                String expression = Console.ReadLine();
                if (expression == "run")
                    break;
                Operation operation = Parse(expression);
                operations.Add(operation);
            }
            foreach (Operation operation in operations)
            {
                Double result = operation.Calculate();
                Console.WriteLine(result);
            }
        }
        private Operation Parse(String expression)
        {
            Double Number1;
            Double Number2;
            Double Number;
            if (expression.Contains('+'))
            {
                String[] numbers = expression.Split('+');
                Number1 = Convert.ToDouble(numbers[0]);
                Number2 = Convert.ToDouble(numbers[1]);
                return new SumOperation(Number1, Number2);
            }
            else if (expression.Contains('-'))
            {
                String[] numbers = expression.Split('-');
                Number1 = Convert.ToDouble(numbers[0]);
                Number2 = Convert.ToDouble(numbers[1]);
                return new MinOperation(Number1, Number2);
            }
            else if (expression.Contains('!'))
            {
                String[] numbers = expression.Split('!');
                Number = Convert.ToDouble(numbers[0]);
                return new Factorial(Number);
            }

            else
            {
                Console.WriteLine("AAAAAAAAAAAAAAA");
                throw new NotImplementedException(); ///Обработка всех непредусмотренных операций.

            }
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            Calculator calculator = new Calculator();
            calculator.StartWork();
            Console.ReadKey();
        }
    }
}