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

  val numbers = List(a,b,c,d,e)

  val max = numbers.max
  val min = numbers.min

  val diff = max - min

  val ans = if (k > max-min) "Yay!" else ":("
  
  println(ans)

}
