import qualified Data.Text as T
import qualified Data.Text.IO as T
import qualified Data.Text.Read as T
import qualified Data.Set as S

main :: IO ()
main = do
  n <- unsafeTextToInt <$> T.getLine :: IO Int
  ss <- sequence . replicate n $ T.getLine :: IO [T.Text]
  print . count $ ss

count :: [T.Text] -> Int
count = S.size . foldl (flip S.insert) S.empty

unsafeTextToInt :: T.Text -> Int
unsafeTextToInt s = case T.signed T.decimal s of
  Right (n, _) -> n
