import scala.io.StdIn

object Main extends App {

  val a = StdIn.readLine().split(" ").map(_.toInt)
  
  def judge(n: Int) = n > 0 && n % 3 == 0 
  
  println(if(judge(a(0)) || judge(a(1)) || judge(a.sum)) "Possible" else "Impossible")
  
}
