import Control.Applicative ((<$>))
import Control.Monad (replicateM)
import Data.Char (digitToInt)

main :: IO ()
main = do
  n <- readLn
  solve <$> replicateM n getLine >>= mapM_ print

solve :: [String] -> [Int]
solve = map $ ft . map digitToInt

ft :: [Int] -> Int
ft [x] = x
ft xxs@(x:xs) = ft $ zipWith (\a b -> let (q,r) = divMod (a + b) 10 in q + r) xxs xs