How to create a list of list of numbers in Haskell

Question

I need to create a function that makes a board of size row and column and then populate that with zeros. mkBoard 2 3 would make [[0,0,0],[0,0,0]]

I don\'t really know w

Answer 1

There is no need to use list comprehension here. We can make use of replicate :: Int -> a -> [a] that will convert an Int n and an a to a list that repeats that value n times.

We thus can construct a list of three 0s with replicate 3 0. We can then use replicate a second time to construct a list that contains that list two times for example.

mkBoard :: Num n => Int -> Int -> [[n]]
mkBoard m n = replicate m (replicate n 0)