using System;

public class Program

{

    public static void Main()

    {

        double a = 0;

        double b = 0;

        Console.WriteLine("Hi!!! Welcome to My First Ever Calculator");

        Console.WriteLine("\n");

        Console.WriteLine("Are u ready To Use it?");

        Console.ReadLine();

        here:

​

        Console.WriteLine("\n");

        Console.WriteLine("Kindly Pick an Operator");

        Console.WriteLine("\n");

        Console.WriteLine("Input + For Addition");

        Console.WriteLine("Input - For Subtraction");

        Console.WriteLine("Input * For Multiplication");

         Console.WriteLine("Input / For Division");

         Console.WriteLine("Input % For Modulo");

           string Input = Console.ReadLine();

            Console.WriteLine("\n");

        if (Input == "+")

        {

            Console.Clear();

            Console.WriteLine (" Input Your First Number:  ");

            a = Convert.ToDouble(Console.ReadLine());

            Console.WriteLine("Input Your Second Number: ");

            b = Convert.ToDouble(Console.ReadLine());

            Console.WriteLine("\n");

            Console.WriteLine("Answer: " +  (a + b ));

            Console.WriteLine("\n");

            Console.Write("Hit Enter To Go back");

            Console.ReadLine();

            Console.Clear();

           goto here;

        }

​

         else if (Input == "-") 

         {

             Console.WriteLine("Input Your First Number:  ");

             a = Convert.ToDouble(Console.ReadLine());

             Console.WriteLine("Input Your Second Number:  ");

             b = Convert.ToDouble(Console.ReadLine());

             Console.WriteLine("\n");

             Console.WriteLine("Answer: " + (a - b));

             Console.WriteLine("\n");

             Console.Write("Hit enter To Go back");

             Console.ReadLine();

             Console.Clear();

             goto here;      

         }

          else if (Input == "*")

          {

               Console.WriteLine("Input Your First Number: ");

              a= Convert.ToDouble(Console.ReadLine());

              Console.WriteLine("Input Your Second Number: ");

              b = Convert.ToDouble(Console.ReadLine());

              Console.WriteLine("\n");

              Console.WriteLine("Answer: " + (a * b ));

              Console.Write("Hit Enter To Go back");

              Console.ReadLine();

              Console.Clear();

             goto here;

          }

           else if (Input == "/")

           {

               Console.WriteLine("Input Your First Number");

               a = Convert.ToDouble(Console.ReadLine());

               Console.WriteLine("Input Your Second Number");

               b = Convert.ToDouble(Console.ReadLine());

               Console.WriteLine("\n");

               Console.WriteLine("Answer: " + ( a / b));

               Console.Write("Hit Enter To Go Back");

               Console.ReadLine();

               Console.Clear();

              goto here;           

           }

              else if(Input == "%")

              {

                  Console.WriteLine("Input Your First Number");

                  a = Convert.ToDouble(Console.ReadLine());

                  Console.WriteLine("Input Your Second Number");

                  b = Convert.ToDouble(Console.ReadLine());

                  Console.WriteLine("\n");

                  Console.WriteLine("Answer: " + ( a % b));

                  Console.Write("Hit Enter To Go Back");

                  Console.ReadLine();

                  Console.Clear();

             goto here;

              }

            else 

            {

                Console.Clear();

                Console.WriteLine("Error");

                Console.WriteLine(" Your Old Enough to understand Mathematical Operation");

                Console.Write("Press Enter To Go Back");

                Console.ReadLine();

                goto here;

            }

​

    }

}