Unique in Haskell

In Haskell, you can get unique elements of an array using the nub function from the Data.List module.

Here is an example:

import Data.List (nub)
main = do

  let arr = [1, 2, 3, 2, 1, 4, 5, 4]

  print $ nub arr

  

-- Output: [1,2,3,4,5]

In this example, we create an array arr with some duplicate elements and then apply the nub function from the Data.List module to get the unique elements of the array.

The nub function takes an array arr as input and returns a new array that contains only the unique elements from arr. The order of the elements in the new array is not defined.

Note that the nub function uses an O(n^2) algorithm to remove duplicates, so it may not be efficient for large arrays. If you need to work with large arrays, you may want to consider using a different data structure or a different algorithm to efficiently remove duplicates.