using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Welcome to my Simple Arithmetic Calculator!");

        Console.WriteLine("Please input the first number.");

        var input = Console.ReadLine();

        Console.WriteLine("You input " + input + ".");

        //See if you can convert the string number1 to a double, if not, do the code in the catch block

        try

        {

            //Convert the string number1 to a double

            double number1 = Double.Parse(input);

            Console.WriteLine("Please input the operation. (Only +, -, /, and *)");

            var operation = Console.ReadLine();

            Console.WriteLine("You input " + operation + ".");

            //See if it is an operation or not

            if(operation == "+" || operation == "-" || operation == "/" || operation == "*")

            {

                Console.WriteLine("Finally, please enter a final number.");

                input = Console.ReadLine();

                Console.WriteLine("You input " + input + ".");

                //See if you can convert the string number2 to a double, if not, do the code in the catch block

                try

                {

                    //Convert the string number2 to a double

                    double number2 = Double.Parse(input);

                    //Next, do the operation

                    if(operation == "+")

                    {

                        var result = number1 + number2;

                        //Display the result of the operation

                        Console.WriteLine("The result of the operation " + number1 + operation + number2 + " was " + result + ".");

                    }

                    else if(operation == "-")

                    {

                        var result = number1 - number2;

                        //Display the result of the operation

                        Console.WriteLine("The result of the operation " + number1 + operation + number2 + " was " + result + ".");

                    }

                    else if(operation == "/")

                    {

                        var result = number1 / number2;

                        //Display the result of the operation

                        Console.WriteLine("The result of the operation " + number1 + operation + number2 + " was " + result + ".");

                    }

                    else

                    {

                        var result = number1 * number2;

                        //Display the result of the operation

                        Console.WriteLine("The result of the operation " + number1 + operation + number2 + " was " + result + ".");

                    }

                }

                catch(FormatException)

                {

                    //Failed

                    Console.WriteLine("Sorry, but we could not understand your input. Did it contain any words or letters?");

                }

            }

            else

            {

                //If it is not an operation

                Console.WriteLine("Sorry, but that doesn't seem to be an operation.");

            }

        }

        catch(FormatException)

        {

            //Failed

            Console.WriteLine("Sorry, but we could not understand your input. Did it contain any words or letters?");

        }

    }

}

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