using System;

public class Program

{

    public static void Main()

    {

        int sum = 0;

        int difference = 0;

        int product = 0;

        int quotient = 0;

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

        int firstnumber = int.Parse(Console.ReadLine());

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

        int secondnumber = int.Parse(Console.ReadLine());

        Console.WriteLine("what operation to want to perform?");

        int result = 0;

        string operation = Console.ReadLine();

        if(operation  == "A" || operation == "a"){

            result = firstnumber + secondnumber;

            Console.WriteLine("You Choose Addition");

            sum = firstnumber + secondnumber;

            Console.WriteLine("The answer is: " + sum);

        }

        if(operation  == "B" || operation == "b"){

            result = firstnumber - secondnumber;

            Console.WriteLine("You Choose Subtraction");

            difference = firstnumber - secondnumber;

            Console.WriteLine("The answer is: " + difference);

        }

        if(operation  == "C" || operation  == "c"){

            result = firstnumber * secondnumber;

            Console.WriteLine("You Choose Multiplication");

            product = firstnumber * secondnumber;

            Console.WriteLine("The answer is: " + product);

        }

        if(operation  == "D" || operation  == "d"){

            result = firstnumber / secondnumber;

            Console.WriteLine("You Choose Division");

            quotient = firstnumber / secondnumber;

            Console.WriteLine("The answer is: " + quotient);

        }

    }

}

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