import java.util.Scanner;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        int numlist[] = new int[5];
        int k = 0;
        boolean isOk = true;
        
        for(int i=0; i<5; i++){
            numlist[i] = sc.nextInt();
        }

        k = sc.nextInt();

        loop:for(int i=0; i<5; i++){
            for(int j=i+1; j<5; j++){
                if((numlist[j]-numlist[i])>k){
                    isOk = false;
                    break loop;
                }
            }
        }
        if(isOk){
            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