import qualified Data.ByteString.Char8 as B
import Data.Maybe(fromJust)

main = B.getContents >>= main' . map readInteger' . B.lines
    where
        main' [a, x] = print (pow' a x `mod` m)
{-
        main' [a, x]
            | a == 0 && x == 0 = return ()
            | otherwise = print (pow' a x `mod` m) >> main
-}
m :: Integer
m = 10

readInteger' :: B.ByteString -> Integer
{-# INLINE readInteger' #-}
readInteger' = fst . fromJust . B.readInteger

pow' :: Integer -> Integer -> Integer
pow' a x
    | x == 0 = 1
    | x > m = pow' a (x `mod` m)
    | a > m = pow' (a `mod` m) x
    | even x = pow' (a * a) (x `div` 2)
    | otherwise = a * pow' a (x - 1)