def show_2d(self):

        a = self._tree.bfs_order_star()
        i = 1
        hojd_pa_trad = self._tree.height()
        just_nu_hojd = 0

        for p in range(len(a)):
            antal = 2**(hojd_pa_trad - just_nu_hojd - 1)

            for x in range(antal):

                print("\t", end='')

            print("{}".format(a[p] if a[p] is not None else "*" ), end = '')

            for x in range(antal):

                print("\t", end='')

            if p + 1 == i:

                print("\n")
                i = i * 2 + 1
                just_nu_hojd = just_nu_hojd + 1