Algo_24_02_2017_T2

public static int Algo_24_02_2017_T2(BST T, BST P, int x)
{
    BST last = null;
    var S = new Stack<BST>();

    var R = new Stack<int>();
    var n_figli = new Stack<bool[]>();
    var ret = 0;

    while (S.Count > 0 || T != null)
        if (T != null)
        {
            n_figli.Push(new bool[] {
                (T.Sx == null ? false : true),
                (T.Dx == null ? false : true)
            });

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

            if (T.Dx != null && T.Dx != last)
                T = T.Dx;
            else
            {
                S.Pop();
                P = (S.Count > 0 ? S.Peek() : null);

                var figli = n_figli.Pop();
                var r_sx = (figli[0] ? R.Pop() : 0);
                var r_dx = (figli[1] ? R.Pop() : 0);

                ret = r_sx + r_dx + 1;
                System.Console.WriteLine($"n: {T.key} | ret: {ret}");

                R.Push(ret);
                last = T;

                if (T.key % 2 == 0 && ret < x && P != null)
                {
                    if (T == P.dx)
                    {
                        P.dx = Cancella(T);
                        last = P.dx;
                    }
                    else
                    {
                        P.sx = Cancella(T);
                        last = P.sx;
                    }
                }

                T = null;
            }
        }

    return ret;
}