static void Main(string[] args)
{
AvlTree <int> tree = new AvlTree <int>();
for (int i = 1; i < 10; i++)
{
tree.Add(i);
}
Console.WriteLine("In-order: " + string.Join(", ", tree.GetInorderEnumerator()));
Console.WriteLine("Post-order: " + string.Join(", ", tree.GetPostorderEnumerator()));
Console.WriteLine("Breadth-first: " + string.Join(", ", tree.GetBreadthFirstEnumerator()));
AvlTreeNode <int> node = tree.FindNode(8);
Console.WriteLine($"Children of node {node.Value} (height = {node.Height}): {node.Left.Value} and {node.Right.Value}.");
}