using System;

class NullableTypes
{
    static void Main()
    {
        int? a = null;
        int b;
        Console.WriteLine(b);
        b = a;
        Console.WriteLine(b);


        Console.WriteLine(
            new string('-', 40) +
            "\nExample with integer\n" +
            new string('-', 40));

        int? someInteger = null;
        string str = "";
        string nullStr = null;
        //int someInteger = null;
        Console.WriteLine(
            "This is the integer with Null value -> " + someInteger);
        someInteger = 5;
        Console.WriteLine(
            "This is the integer with value 5 -> " + someInteger);

        Console.WriteLine(
            new string('-', 40) +
            "\nExample with double\n" +
            new string('-', 40));

        double? someDouble;
        //double someDouble;
        someDouble = null;
        Console.WriteLine(
            "This is the floating-point number with Null value -> " + someDouble);
        someDouble = 2.5;
        Console.WriteLine(
            "This is the floating-point number with value 2.5 -> " + someDouble);

        int? value = null;
        Console.WriteLine(value.GetValueOrDefault());

        // Console.WriteLine(value.Value); // This will cause an exception
    }
}