static void Main(string[] args)
{
grandfather[] arr = new grandfather[3];
arr[0] = new grandfather();
arr[1] = new father();
arr[2] = new son();
for (int i = 0; i < 3; i++)
{
Console.WriteLine(arr[i].hello());
}
//------------
ArrayList l = new ArrayList();
l.Add(new grandfather());
l.Add(new father());
l.Add(new son());
//l.Add(5);
for (int i = 0; i < 3; i++)
{
Console.WriteLine((l[i] as grandfather).hello());
}
foreach (grandfather item in l)
{
Console.WriteLine((item as grandfather).hello());
}
}
static void Main(string[] args)
{
grandfather[] arr = new grandfather[3];
arr[0] = new grandfather();
arr[1] = new father();
arr[2] = new son();
for (int i = 0; i < 3; i++)
{
Console.WriteLine(arr[i].hello());
}
}