Archive for September, 2010
Project Euler Problem 22
0Whilst trying Project Euler problems, I often write a prototype in Python before trying out an implementation in Haskell.
This problem however was screaming for “Functional Programming”.
In fact this time around, I started with a Haskell implementation and went on to translate to Python just for kicks. 🙂
Suffice to say, I am very pleased with myself. 😀
import Char
import List
names = [<List of names from problem specification>]
{- For each string s in list, Calculate sum of the characters’ alpha positions -}
sumChars :: [String] -> [Int]
sumChars [] = []
sumChars (x:xs) =
(foldl (\acc ltr -> acc + (ord(ltr)-ord(‘A’) + 1)) 0 x) : sumChars xs
main = do
let sortedNames = sort(names)
let zippedSumAndIndex = zip [1 .. length(sortedNames)] (sumChars sortedNames)
let total = foldl (\x y -> x + fst(y) * snd(y)) 0 zippedSumAndIndex
print total