using System;

public class Program

{

    public static void Main(string [] args)

        {

            int a;

        int b;

        int c;

            Console.WriteLine("Arithetic op");

            Console.WriteLine("Values");

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

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

        Console.WriteLine("1. Add");

        Console.WriteLine("2. Sub");

        Console.WriteLine("3. Multiplication");

        Console.WriteLine("4. Division");

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

        Switch(c)

        {

                case1:

                Console.WriteLine("Add of 2nos:"+(a+b));

                break;

                case2:

                Console.WriteLine("Sub of 2 nos :"+(a-b));

                break;

                case3:

                Console.WriteLine("Multiply of 2nos :"+(a*b));

                break;

                Case4:

                Console.WriteLine("Divide of 2 nos :"+(a/b));

                break;

            default:

                Console.WriteLine("Null");

                break;

        }

        Console.ReadLine();

    }

}