using System;

​

namespace Calculator_thing

{

​

    enum OperationsEnum

    {

        Addition, Subtraction, Multiplication, Division, Squareroot, Squared

    }

​

    class Program

    {

        static void Main(string[] args)

        {

            while (true)

            {

                Console.WriteLine("Please enter your first number.");

                double operand1 = ReadDouble();

​

                Console.WriteLine("What operation do you want to use?");

                OperationsEnum operation = ReadOperationsEnum();

​

                if (IsUnary(operation))

                {

                    double result = Calculate1(operand1, operation);

                    Console.WriteLine(result);

                    Console.ReadLine();

​

                }

                else

                {

                    Console.WriteLine("Please enter your second number.");

                    double operand2 = ReadDouble();

​

                    double result = Calculate(operand1, operation, operand2);

                    Console.WriteLine(result);

                    Console.ReadLine();

                }

            }

        }

        static bool IsUnary(OperationsEnum operation)

        {

            if (operation == OperationsEnum.Squareroot) return true;

            if (operation == OperationsEnum.Squared) return true;

            else return false;

​

        }

​

       static double Calculate1(double operand1, OperationsEnum operation)

        {

            if (operation == OperationsEnum.Squared) return operand1 * operand1;

            if (operation == OperationsEnum.Squareroot) return Math.Sqrt(operand1);

            else return Math.Sqrt(operand1);

        } 

​

        static double Calculate(double operand1, OperationsEnum operation, double operand2)

        {

            if (operation == OperationsEnum.Addition) return operand1 + operand2;

            if (operation == OperationsEnum.Subtraction) return operand1 - operand2;

            if (operation == OperationsEnum.Multiplication) return operand1 * operand2;

            else return operand1 / operand2;

        }

    static double ReadDouble()

        {

            string input = Console.ReadLine();

            return double.Parse(input);

        }

        static OperationsEnum ReadOperationsEnum()

        {

            while (true)

            {

                Console.WriteLine("SR - square root ");

                Console.WriteLine("XX - squared ");

                Console.WriteLine("+ - addition ");

                Console.WriteLine("- - subtraction");

                Console.WriteLine("*- multiplication");

                Console.WriteLine("/ - division");

​

                string input = Console.ReadLine();

                if (input == "+")

                {

                    return OperationsEnum.Addition;

                }

                if (input == "-")

                {

                    return OperationsEnum.Subtraction;

                }

                if (input == "*")

                {

                    return OperationsEnum.Multiplication;

                }

                if (input == "/")

                {

                    return OperationsEnum.Division;

                }

                if (input == "SR")

                {

                    return OperationsEnum.Squareroot;

                }

                if (input == "XX")

                {

                    return OperationsEnum.Squared;

                }

            }

​

​

        }

    }

}