import scala.io.StdIn._

object Main extends App {
  val n = 5
  val a = (1 to n).map(_ => readLine.toInt).toArray
  val k = readLine.toInt
  var msg = "Yay!"
  for (i <- (4 to 1 by -1)) {
    if (a(i) - a(0) > k) {
      msg = ":("
    }
  }
  println(msg)
}