ue2_5

namespace ConsoleApplication13
{
    class Program
    {
        static void Main(string[] args)
        {
            double a, b;
            double result;
            int op;

            Console.WriteLine("Enter the 1st number:");
            a = double.Parse(Console.ReadLine());

            Console.WriteLine("Enter the 2nd number:");
            b = double.Parse(Console.ReadLine());

            Console.WriteLine("Enter the operators a & b:");
            Console.WriteLine("\n  1 = +\n  2 = -\n  3 = *\n  4 = /");

            op = Convert.ToInt32(Console.ReadLine());

            switch (op)
            {
                case 1:
                    result = a + b;
                    break;
                case 2:
                    result = a - b;
                    break;
                case 3:
                    result = a * b;
                    break;
                case 4:
                    result = a / b;
                    break;
                default:
                    result = 0;
                    break;
            }
            Console.WriteLine("\n result:{0}", result);
            Console.ReadLine();
        }
    }
}