main :: [sys_message]
main = [Stdout (lay (map show (comb 3 5)))]

comb :: num->num->[[num]]
comb m n = comb' m [0..n-1]
           where comb' 0 xs     = [[]]
                 comb' m []     = []
                 comb' m (x:xs) = map (x:) (comb' (m-1) xs) ++ comb' m xs