import java.util.Scanner

object Main {
  val sc = new Scanner(System.in)
  def main(args: Array[String]): Unit = {
    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 res = if(e - a <= k) "Yay!" else ":("

    println(res)
  }
}