Thus, in both cases, we need to make sure that a transition is applied during training only if it is considered correct by the oracle; else we cannot guarantee that later oracle predictions will be correct.
on line 9, we either remain in the same configuration (easyfirst) or follow the oracle prediction and go to t o (c) (left-to-right systems); on line 11, we in fact also go to t o (c), because in this case we have t p (c) = t o (c).