private static void TestingICloneable()
{
int[] elements = { 1, 2, 3, 4, 5 };
IntegerSet s1 = new IntegerSet(elements);
Console.WriteLine("s1: {0}", s1);
IntegerSet s2 = (IntegerSet)s1.Clone();
Console.WriteLine("s2: {0}", s2);
s2.Remove(5);
Console.WriteLine("s2: {0}", s2);
}
