On 6/13/06, Jenny678 wrote:

Hallo I search a code for

...

elements_in_List([1,2],[1,2]). True elements_in_List([1,8],[1,2,3,4,8]). True elements_in_List([2,1],[1,2]). True elements_in_List([1,1],[1]). False

I have a code elements_in_List :: Eq a => [a] -> [a] -> Bool elements_in_List [] _ = True elements_in_List _ [] = False elements_in_List (x:xs) (y:ys) | x == y = elements_in_List xs ys | True = elements_in_List (x:xs) ys

but it failed at

...

elements_in_List([2,1],[1,2]). True

I hope somebody can help me Please don't use built-in-Functions.

Thanks for Help

I haven't looked too far into this, but how about something like this: elements_in_list a b = and $ map (\x -> element_in_list x b) a where element_in_list = ... Maybe if you don't want to use built-in functions, define your own 'and' as well. Bryan