fun main (args: Array<String>) {
	var num1 : String?
	var num2 : Int
	
	var list : MutableList<Int> = mutableListOf()
	var count : Int = 0
	
	for (i in 0..4) {
		num1 = readLine()
		num2 = num1!!.toInt()
		list.add(num2)
	}
	
	val num3 = readLine()
	val k = num3!!.toInt()
	
	var p : Int
	var q : Int
	
	for (i in 0..list.size - 1) {
		p = list[i]
		for (j in 0..list.size - 1) {
			q = list[j]
			if ( (p-q)>k || (p-q)<-k ) {
				count++
			}
		}
	}
	
	if (count >= 1) {
		println(":(")
	} else {
		println("Yay!")
	}
	
}