import java.util.*;

public class Main {

	public static void main(String[] args) {
		
		Scanner sc = new Scanner(System.in);
		
		int a = sc.nextInt();
		int b = sc.nextInt();
		int c = sc.nextInt();
		int d = sc.nextInt();
		int e = sc.nextInt();
		int k = sc.nextInt();
		
		if (Math.abs(a - b) <= k && Math.abs(a-c) <= k && Math.abs(a-d) <= k && Math.abs(a-e) <=k
				&& Math.abs(b-c) <=k && Math.abs(b-d) <= k && Math.abs(b-e) <= k && Math.abs(c-d) <=k
				&& Math.abs(d-e) <= k) {
			System.out.println("Yay!");
		}else {
			System.out.println(":(");
		}
		
	}

}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz