navigazione iterativa

public static void PreOrder_Ricorsivo(BST T, Action<BST> Action_PreOrder)
{
    if (T != null)
    {
        Action_PreOrder(T);
        PreOrder_Ricorsivo(T.Sx, Action_PreOrder);
        PreOrder_Ricorsivo(T.Dx, Action_PreOrder);
    }
}

public static void InOrder_Ricorsivo(BST T, Action<BST> Action_InOrder)
{
    if (T != null)
    {
        InOrder_Ricorsivo(T.Sx, Action_InOrder);
        Action_InOrder(T);
        InOrder_Ricorsivo(T.Dx, Action_InOrder);
    }
}

public static void PostOrder_Ricorsivo(BST T, Action<BST> Action_PreOrder, Action<BST> Action_InOrder, Action<BST> Action_PostOrder)
{
    if (T != null)
    {
        Action_PreOrder(T);
        PostOrder_Ricorsivo(T.Sx, Action_PreOrder, Action_InOrder, Action_PostOrder);
        Action_InOrder(T);
        PostOrder_Ricorsivo(T.Dx, Action_PreOrder, Action_InOrder, Action_PostOrder);
        Action_PostOrder(T);
    }
}

public static void PreOrder_Iterativo(BST T, Action<BST> Action_PreOrder)
{
    var S = new Stack<BST>();

    while (S.Count > 0 || T != null)
        if (T != null)
        {
            Action_PreOrder(T);
            S.Push(T);
            T = T.Sx;
        }
        else
        {
            T = S.Peek();
            T = T.Dx;
            S.Pop();
        }
}

public static void PostOrder_Iterativo(BST T, Action<BST> Action_PreOrder, Action<BST> Action_InOrder, Action<BST> Action_PostOrder)
{
    BST last = null;
    var S = new Stack<BST>();

    while (S.Count > 0 || T != null)
        if (T != null)
        {
            Action_PreOrder(T);

            S.Push(T);
            T = T.Sx;
        }
        else
        {
            T = S.Peek();

            if (T.Dx != null && T.Dx != last)
            {
                Action_InOrder(T);

                T = T.Dx;
            }
            else
            {
                Action_PostOrder(T);

                last = T;
                T = null;
                S.Pop();
            }
        }
}

public static void InOrder_Iterativo(BST T, Action<BST> Action_InOrder)
{
    var S = new Stack<BST>();

    while (S.Count > 0 || T != null)
        if (T != null)
        {
            S.Push(T);
            T = T.Sx;
        }
        else
        {
            T = S.Pop();
            Action_InOrder(T);
            T = T.Dx;
        }
}