import Control.Monad
 
uniqList :: Eq a => [a] -> [a]
uniqList []     = []
uniqList (x:xs) = (if x `elem` xs then [] else [x]) ++ (uniqList xs)
 
main :: IO ()
main = do
 n <- readLn
 s <- replicateM n getLine
 print $ length $ uniqList s
