import scala.io.{StdIn => in}

object Main extends App {
  val a = Iterator.continually(in.readInt)
    .take(5)
    .toArray
  val k = in.readInt
  val ans = if(Array(0,1,2,3,4).combinations(2).forall(i => (a(i(0)) - a(i(1))).abs <= k)) "Yay!" else ":("
  println(ans)
}