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(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("Yay!");
      }else{
	System.out.println(":(");        
      }
      }
} import java.util.*; util.* java 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(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("Yay!");
      }else{
	System.out.println(":(");        
      }
      }
} 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(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("Yay!");
      }else{
	System.out.println(":(");        
      }
      } main {
    
    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(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("Yay!");
      }else{
	System.out.println(":(");        
      }
      } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int a = sc.nextInt(); a sc.nextInt() sc.nextInt sc int b = sc.nextInt(); b sc.nextInt() sc.nextInt sc int c = sc.nextInt(); c sc.nextInt() sc.nextInt sc int d = sc.nextInt(); d sc.nextInt() sc.nextInt sc int e = sc.nextInt(); e sc.nextInt() sc.nextInt sc int k = sc.nextInt(); k sc.nextInt() sc.nextInt sc 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("Yay!");
      }else{
	System.out.println(":(");        
      } 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 e-c<=k d-c<=k e-b<=k d-b<=k c-b<=k e-a<=k d-a<=k 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 b-a<=k b-a b a k c-a<=k c-a c a k d-a<=k d-a d a k e-a<=k e-a e a k c-b<=k c-b c b k d-b<=k d-b d b k e-b<=k e-b e b k d-c<=k d-c d c k e-c<=k e-c e c k e-d<=k e-d e d k {
 	System.out.println("Yay!");
      } System.out.println("Yay!") System.out.println System.out System System.out "Yay!" {
	System.out.println(":(");        
      } System.out.println(":(") System.out.println System.out System System.out ":(" String[] args args 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(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("Yay!");
      }else{
	System.out.println(":(");        
      }
      }
} 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(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("Yay!");
      }else{
	System.out.println(":(");        
      }
      }
} Main
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(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("Yay!");
      }else{
	System.out.println(":(");        
      }
      }
}