public void AllEqual()
{
Grandfather g1 = new Grandfather();
Grandfather f1 = new Father();
Grandfather s1 = new Son();
Assert.AreEqual(g1.LastName(), f1.LastName(), s1.LastName());
}
public void NoneEqual()
{
Grandfather g1 = new Grandfather();
Father f1 = new Father();
Son s1 = new Son();
Assert.AreNotEqual(
g1.LastName(),
f1.LastName(),
s1.LastName());
}