import Control.Monad
import Data.List
import qualified Data.ByteString.Char8 as BS
import qualified Data.Set as Set

main :: IO ()
main = do
  n <- readLn
  s <- replicateM n BS.getLine
  print $ length $ ordNub s
  
ordNub :: Ord a => [a] -> [a]
ordNub xs = foldr (\x k s -> if Set.member x s then k s else x:k(Set.insert x s)) (const[]) xs Set.empty