fizzbuzz.hs

module Main where

import Data.Maybe (fromMaybe)

main :: IO ()
main = print $ map fizzbuzz [1..110]

fizzbuzz :: Int -> String
fizzbuzz n = fromMaybe (show n) $ (fizz <> buzz <> diffie) n

fizz :: Int -> Maybe String
fizz = modStr 3 "Fizz"

buzz :: Int -> Maybe String
buzz = modStr 5 "Buzz"

diffie :: Int -> Maybe String
diffie = modStr 7 "Diffie"

modStr :: Int -> String -> Int -> Maybe String
modStr n str input
  | input `mod` n == 0 = Just str
  | otherwise = Nothing

instead of structuring it the classic way with guards and mod 3, mod 5, mod 15, this way allows for additional numbers/strings with ease - which is quite often a follow up question in interviews. here i've added 7 to show my cats name!