def dfs(self):
        closedset = set()
        fringle = util.Stack()
        fringle.push(self.fromNode)
        while fringle.isEmpty() == 0:
            state, path = (fringle.pop(),[])
            if (self.isGoalState(state)):
                return path
            if (state not in closedset):
                closedset.add(state)
                for i in self.getSuccessors(state, set):
                    fringle.push((i[0], path + [i[1]]))