using System;

public class Program

{

    public static void Main()

    {

        do

            {

        Console.Write("operators ");//operators

        Console.Write("(a)for addition, ");

        Console.Write("(x)for multiplication, ");

        Console.Write("(d)for division, ");

        Console.Write("(s)for subtraction, ");

        Console.Write("(b)for exit ");

                string ope = Console.ReadLine();

                if (ope == "b")

                {

                    Console.WriteLine("Program has stopped");

                    break;

                }

                else if (ope == "a")//code for addition

                {

                Console.Write("num1 = ");

                 string str = Console.ReadLine();

                    int x = Convert.ToInt32(str);

                    Console.Write("num2 = ");

                    int y = Convert.ToInt32(Console.ReadLine());

                    int sum = x + y;

                    Console.WriteLine("Result: {0}", sum);

                }

                else if (ope == "x")//code for multiplication

                {

                Console.Write("num1 = ");

                 string str = Console.ReadLine();

                    int x = Convert.ToInt32(str);

                    Console.Write("num2 = ");

                    int y = Convert.ToInt32(Console.ReadLine());

                    int mul = x * y;

                    Console.WriteLine("Result: {0}", mul);

                }

                else if (ope == "d")//code for division

                {

                Console.Write("num1 = ");

                 string str = Console.ReadLine();

                    int x = Convert.ToInt32(str);

                    Console.Write("num2 = ");

                    int y = Convert.ToInt32(Console.ReadLine());

                    int div = x / y;

                    Console.WriteLine("Result: {0}", div);

                }

            else if (ope == "s")//code for subtraction

                {

                Console.Write("num1 = ");

                 string str = Console.ReadLine();

                    int x = Convert.ToInt32(str);

                    Console.Write("num2 = ");

                    int y = Convert.ToInt32(Console.ReadLine());

                    int min = x - y;

                    Console.WriteLine("Result: {0}", min);

                }

                else 

                {

                    Console.Write("error");

                    break;

                }

​

            }

            while (true);

}

}