Haskell generating all combinations of n numbers

Question

I am trying to generate all possible combinations of n numbers. For example if n = 3 I would want the following combinations:

(0,0,0), (0,0,1), (0,0,2)... (0,0,9         


        

Answer 1

combos 1 list = map (\x -> [x]) list
combos n list = foldl (++) [] $ map (\x -> map (\y -> x:y) nxt) list
    where nxt = combos (n-1) list

In your case

combos 3 [0..9]