import java.util.*;

class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);

        int[] ant = new int[5];
        int k;
        boolean judge =true;
        int A = 0;

        for(int i = 0;i < ant.length;i++){
            ant[i] = sc.nextInt();
        }

        k = sc.nextInt();

        for(int i = 0;i < ant.length;i++){
            for(int j = i+1;j < ant.length;j++){
                A = ant[j] - ant[i];
                if(k < A)
                    judge = false;
            }
        }

        if(judge == false){
            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