import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int antennaAmounts = 5;
		int[] antennas = new int[antennaAmounts];
		
		for(int i = 0 ; i < antennaAmounts ; i++) {
			antennas[i] = sc.nextInt();
		}
		int inputK = sc.nextInt();
		sc.close();
		
		if(antennas[antennaAmounts-1] - antennas[0] <= inputK) {
			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