excel_cols.hs

module Main where

import System.Environment

l v = f (reverse v) - 1
  where
    f ([]) = 0
    f (x:xs) = (nmap x + 1) + baseLen * f xs
    nmap x = fromJust $ lookup x $ zip base [0..]
    base = ['a'..'z']
    baseLen = length base

main :: IO ()
main = do
    (v:_) <- getArgs

    print $ l v