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

solve :: Int -> Int -> String
solve a b
  | (a `mod` 3 == 0) ||
    (b `mod` 3 == 0) ||
    ((a + b) `mod` 3 == 0) = "Possible"
  | otherwise = "Impossible"