module Exercise_8 where

import Data.List

{-WETT-}
{-
shoefa cs = go (filter(/=0) cs) 
    where go [] = 0
          go (x:[]) = 0  
          go (x:y:xs) = if x*y < 0 then 1 + go (y:xs) else go (y:xs)
            
-}

shoefa xs = length (filter (<0) (zipWith (*) cs  $ tail cs))
  where cs = filter (/=0) xs

{-TTEW-}