Problem22.hs

import Data.List
import Data.List.Split
import Data.Maybe
import Data.Char

{-

  http://projecteuler.net/index.php?section=problems&id=22
  
  Using names.txt (right click and 'Save Link/Target As...'), a 46K text file containing over five-thousand first names, begin by sorting it into alphabetical order. Then working out the alphabetical value for each name, multiply this value by its alphabetical position in the list to obtain a name score.

  For example, when the list is sorted into alphabetical order, COLIN, which is worth 3 + 15 + 12 + 9 + 14 = 53, is the 938th name in the list. So, COLIN would obtain a score of 938  53 = 49714.

  What is the total of all the name scores in the file?

-}

getNamesAZ :: [Char] -> [String]
getNamesAZ text = f names
  where 
    names = splitOn "," text
    f = sort . map read

getLetterScore :: Char -> Int
getLetterScore x = (ord x) - 64

getNameScore :: [String] -> String -> Int
getNameScore names name = nameWeight * lettersWeight
  where
    f acc x = acc + (getLetterScore x)
    index = elemIndex name names
    nameWeight = (fromJust index) + 1
    lettersWeight = foldl f 0 name 
  

getTotalNameScore :: [String] -> Int
getTotalNameScore names = foldl f 0 names
  where
    f acc name = acc + (getNameScore names name)

  

main = do 
  text <- readFile "names.txt"
  print $ f text
  where
    f names = getTotalNameScore . getNamesAZ $ names