using System;

public class Program

{

    public static void Main(string[] args)

    {

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

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

        Console.Write("Enter Operator ");

        String op = Console.ReadLine();

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

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

        if (op =="+") 

        {

            Console.WriteLine(num1 + num2);

        } else if (op =="-")

        {

            Console.WriteLine(num1 - num2);

        }else if (op =="/") 

        {

            Console.WriteLine(num1 / num2);

        } else if (op =="*")

        {

            Console.WriteLine(num1 * num2);

        }else if (op =="*"){  

        }

            else

        {

            Console.WriteLine("Invalid Operation");

            }

        Console.ReadLine();

    }}