import qualified Control.Monad as M
import qualified Data.Char as C

main = do
    t <- readLn
    s <- M.replicateM t getLine
    let s' = map (\x -> map C.digitToInt x) s
    putStr $ unlines $ map (show . solve) s'

solve :: [Int] -> Int
solve s =
    case length s of
         1 -> head s
         otherwise -> solve (f s)

f :: [Int] -> [Int]
f s = map toDigit s'
    where s' = map (\x -> fst x + snd x) $ zip (init s) (tail s)

toDigit :: Int -> Int
toDigit n =
    if n >= 10
       then toDigit $ sum $ map C.digitToInt $ show n
       else n