import java.util.*;


public class Main {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);
        int n = 5;
        int[] positions = new int[n];
        for (int i = 0; i < n; i++) {
            positions[i] = sc.nextInt();
        }
        
        int border = sc.nextInt();
        boolean pass = true;
        
        for (int i = 0; i < n - 1; i++) {
            for (int j = i + 1; j < n; j++) {
                int difference = positions[j] - positions[i];
                if (difference > border) {
                    pass = false;
                    break;
                }
            }
        }
        
        if (pass) {
            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