using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        Console.WriteLine("Welcome to the calculator!\nEnter the operation (+, *, /, -)");

        string operation = Console.ReadLine();

        while (operation.Length != 1)

        {

            Console.WriteLine("Invaild, try again");

            operation = Console.ReadLine();

        }

        char charOperation = Convert.ToChar(operation);

        Console.WriteLine("Enter the first num! ");

        int num1 = Convert.ToInt32(Console.ReadLine());

        int num2 = Convert.ToInt32(Console.ReadLine());

        if (charOperation == "+")

        {

        Console.WriteLine("h");

        }

​

​

    }

}