import scala.io.{StdIn => in}
import scala.annotation.tailrec

object Main extends App {
  val Array(_, k) = in.readLine.split(" ").map(_.toInt)
  val a = in.readLine.split(" ").map(_.toInt)
  
  @tailrec
  def gcd(a:Int, b:Int):Int = {
    if(b == 0) a
    else gcd(b, a%b)
  }

  val res = a.reduce( gcd )
  val diff = a.filter(_ >= k).map(_ - k)

  val ans = diff match {
    case d if(d.isEmpty) => "IMPOSSIBLE"
    case d if(d.exists(_ % res == 0)) => "POSSIBLE"
    case _ => "IMPOSSIBLE"
  }

  println(ans)
}