static void Main(string[] args)
{
A a = new A();
B b = new B();
var c = new A.C();
Console.WriteLine("a.value1 : " + a.value1);
Console.WriteLine("b.value1 : " + b.value1);
Console.WriteLine("b.value2 : " + b.Getvalue2()); // or b.Getvalue2(), c.Getvalue2()
Console.WriteLine("c.value3 : " + c.Getvalue3());
}
