On Tue, 6 Jun 2006 [EMAIL PROTECTED] wrote: > Hi, > > I need a functions which takes as argument a list of lists like this one: > > [[1,2],[3],[4]] > > and gives me a list of list with all the possible combinations like this one: > > [[1,3,4],[2,3,4]] > > In this case there are only 2 combinations but if there was more than one > element in the other lists the results were much more.
Using the List instance of monads you can simplify things. foldr (Monad.liftM2 (:)) [[]] [[1,2],[3],[4]] > I'm a little stuck in this simple problem. > > First i was thinking in cartesian product but then i realized that i may > not be what i really need. cartesian product can be computed by liftM2 (,) _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
