import Control.Applicative

main :: IO ()
main = do
    [a, b] <- map read . words <$> getLine
    putStrLn $ solve a b

solve :: Int -> Int -> String
solve a b = if mod a 3 == 0 || mod b 3 == 0 || mod (a+b) 3 == 0 then "Possible" else "Impossible"