using System;

public class Program{

    public class Person

    {

        public string Name { get; set; }

        public int Age { get; set; }

        public Person(string name, int age)

        {

            Name = name;

            Age = age;

        }

    };

    public static void Main()

    {

        Person p1 = new Person("Wallace", 75);

        Person p2 = new Person(null, 42);

        p2.Age = 75;

        string t = p2.Name ?? "is null";

        if (p2.Name == null) {

            Console.WriteLine(t);

        }

        Console.WriteLine(p1.Name ?? "is null");

    }

}