object Main extends App {
  
  var count : Array[Int] = new Array(5)
  count(0) = readInt
  count(1) = readInt
  count(2) = readInt
  count(3) = readInt
  count(4) = readInt
  var k = readInt
  var flag = 0
  for(i <- 0 to count.size - 1) {
    for(j <- 1 to count.size - 1) {
      if(count(j) - count(i) > k)
      flag=1
    }
  }
  println(if(flag!=1){"Yay!"}else{":("})
}