using System;

​

public class Program

{

  public static void Main()

  {

​

    // ineractive part

​

    Console.Write("Enter a number: ");

    double num1 = Convert.ToDouble(Console.ReadLine());

    Console.Write("Enter another number: ");

    double num2 = Convert.ToDouble(Console.ReadLine());

    Console.Write("Specify which mathematics symbol you want to use: ");

    char mathSign = Convert.ToChar(Console.ReadLine());

​

    double answer = 0;

​

    // showing of work part

​

    switch(mathSign)

    {

      case '+':

        answer = num1+num2;

        Console.WriteLine("  " + num1);

        Console.WriteLine("+ " + num2);

        Console.WriteLine("------");

        Console.WriteLine("  " + answer);

        break;

      case '-':

        answer = num1-num2;

        Console.WriteLine("  " + num1);

        Console.WriteLine("- " + num2);

        Console.WriteLine("------");

        Console.WriteLine("  " + answer);

        break;

      case 'x':

        answer = num1*num2;

        Console.WriteLine("  " + num1);

        Console.WriteLine("x " + num2);

        Console.WriteLine("------");

        Console.WriteLine("  " + answer);

        break;

      case '/' or '÷':

        answer = num1/num2;

        Console.WriteLine(num1);

        Console.WriteLine("÷ " + num2);

        Console.WriteLine("------");

        Console.WriteLine(answer);

        break;

    default:

      Console.WriteLine("Invalid symbol");

      break;

    }

​

    Console.WriteLine($"{num1} {mathSign} {num2} = {answer}");

  }

}

​