>>54
yeah, that's cool, but that takes special knowledge about what f is, and you are using a different algorithm to calculate the same result, and this different algorithm is either very efficient or can be easily parallelized. One example of an f I was thinking of would be expanding the frontier in breadth first search. One can't expand the next frontier until the current one is known. Although the frontier can be expanded in parallel, so there are opportunities for parallelization there. But there is a sequential nature to growing a path, where the growth must always go into directions that you have not yet been to. You don't know where not to go, until you've gotten there.