import java.util.Scanner;

public class Main{
	static public void  main(String[] args){
		Scanner scan = new Scanner(System.in);
		int[] p = new int[5];
		for(int i = 0; i < 5; i++){
			p[i] = scan.nextInt();
		}
		int k = scan.nextInt();
		String ret = "Yay!";
		for(int i = 0; i < 4; i++){
			for(int j = i+1; j < 5; j++){
				if(p[j] - p[i] > k) ret=":(";
			}
}
		System.out.println(ret);
	}
}

/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