Hi Dr. Pollett, In the Ignore Delete List Heuristic. the lecture notes say, "Another heuristic we can use in searching for solutions to planning problems is to remove all the delete lists from the effects of all actions." Since a goal can have negated literals, my assumption is that negated goal literals are not dropped from the effects in this heuristic; another approach I assume could be to ignore negated literals in the goal. Is that correct? Thanks, Zayd

-- Ignore Delete Lists Heuristic

As part of the ignore delete list heuristic you should delete nagted literal from the goal.