module Exercise_6 where

import Control.Arrow
import Control.Monad
import Data.Function
import Data.List
import Data.Maybe
import Data.Ratio
import GHC.Num

{-MCCOMMENT
If it wasn't for requiring the starting value in the list as well, I'd have the following 30-token solution using unfoldr:
traceFractran fs = unfoldr `id` \n -> join (,) . numerator <$> find (eqInteger 1 . denominator) `id` map (fromIntegral n *) fs
But alas, I was bested again it seems.
-}
{-WETT-}
traceFractran :: [Rational] -> Integer -> [Integer]
traceFractran fs n = n : (traceFractran fs . numerator & maybe [] $ eqInteger 1 . denominator & find $ map (fromIntegral n *) fs)
{-TTEW-}