Numbers.cs

using System;

namespace Theory_9
{
    class Numbers
    {
        static void Main(string[] args)
        {
            System.Nullable<int> numOne = 10;
            System.Nullable<int> numTwo = null;
            System.Nullable<int> result = numOne + numTwo;

            if (result.HasValue == true)
            {
                Console.WriteLine("Result: " + result);
            }
            else
            {
                Console.WriteLine("Result: null");
            }
        }
    }
}