import java.util.Scanner;

class Main {

  public static void main(String[] args) {
    new Main().run();
  }

  private static Scanner sc = new Scanner(System.in);

  private void run() {
    int a = Integer.parseInt(sc.next());
    int b = Integer.parseInt(sc.next());
    int c = Integer.parseInt(sc.next());
    int d = Integer.parseInt(sc.next());
    int e = Integer.parseInt(sc.next());
    int k = Integer.parseInt(sc.next());

    if (b - a > k || c - a > k || d - a > k || e - a > k || c - b > k || d - b > k || e - b > k || d - c > k || e - c > k || e - d > k) {
      System.out.println(":(");
    } else {
      System.out.println("Yay!");
    }
  }
}

/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