object Main extends App {
  val sc = new java.util.Scanner(System.in)
  val a = sc.nextInt
  val b = sc.nextInt
  val c = sc.nextInt
  val d = sc.nextInt
  val e = sc.nextInt
  val k = sc.nextInt
  if (e - a > k) {
    println(":(")
  } else {
    println("Yay!")
  }
}