-- Question A

import Control.Applicative
import Control.Monad

main = do
  [a, b] <- map read . words <$> getLine
  putStrLn $ show (check a b)
  
check :: Int -> Int -> String
check x y
 | x `mod` 3 == 0 = "Possible"
 | y `mod` 3 == 0 = "Possible"
 | (x+y) `mod` 3 == 0 = "Possible"
 | otherwise = "Impossible"