import qualified Data.Set as Set
import Data.IORef
import Control.Monad

main :: IO ()
main = do
  n <- read <$> getLine :: IO Int
  itemsRef <- newIORef Set.empty :: IO (IORef (Set.Set String))
  forM_ [1..n] $ \i -> do
    str <- getLine
    modifyIORef' itemsRef (Set.insert str)
  items <- readIORef itemsRef
  print $ Set.size items
