import java.util.*;
public class Main {
  public static void main(String[] args){

    Scanner sc = new Scanner(System.in);

    int[] arr = new int[5];

    for (int i = 0; i < 5; i++) {
      arr[i] = sc.nextInt();
    }

    int k = sc.nextInt();
    
    String result = "Yay!";

    loop: for (int i = 0; i < 5; i++) {
      for (int j = i + 1; j < 5; j++) {
        if (k < (arr[j] - arr[i])) {
          result = ":(";
          break loop;
        }
      }
    }

    System.out.println(result);

  }
} import java.util.*; util.* java public class Main {
  public static void main(String[] args){

    Scanner sc = new Scanner(System.in);

    int[] arr = new int[5];

    for (int i = 0; i < 5; i++) {
      arr[i] = sc.nextInt();
    }

    int k = sc.nextInt();
    
    String result = "Yay!";

    loop: for (int i = 0; i < 5; i++) {
      for (int j = i + 1; j < 5; j++) {
        if (k < (arr[j] - arr[i])) {
          result = ":(";
          break loop;
        }
      }
    }

    System.out.println(result);

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

    Scanner sc = new Scanner(System.in);

    int[] arr = new int[5];

    for (int i = 0; i < 5; i++) {
      arr[i] = sc.nextInt();
    }

    int k = sc.nextInt();
    
    String result = "Yay!";

    loop: for (int i = 0; i < 5; i++) {
      for (int j = i + 1; j < 5; j++) {
        if (k < (arr[j] - arr[i])) {
          result = ":(";
          break loop;
        }
      }
    }

    System.out.println(result);

  } main {

    Scanner sc = new Scanner(System.in);

    int[] arr = new int[5];

    for (int i = 0; i < 5; i++) {
      arr[i] = sc.nextInt();
    }

    int k = sc.nextInt();
    
    String result = "Yay!";

    loop: for (int i = 0; i < 5; i++) {
      for (int j = i + 1; j < 5; j++) {
        if (k < (arr[j] - arr[i])) {
          result = ":(";
          break loop;
        }
      }
    }

    System.out.println(result);

  } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int[] arr = new int[5]; arr new int[5] 5 for (int i = 0; i < 5; i++) {
      arr[i] = sc.nextInt();
    } int i = 0; int i = 0; i 0 i < 5 i 5 i++ i++ i {
      arr[i] = sc.nextInt();
    } {
      arr[i] = sc.nextInt();
    } arr[i] = sc.nextInt() arr[i] arr i sc.nextInt() sc.nextInt sc int k = sc.nextInt(); k sc.nextInt() sc.nextInt sc String result = "Yay!"; result "Yay!" System.out.println(result) System.out.println System.out System System.out result String[] args args public class Main {
  public static void main(String[] args){

    Scanner sc = new Scanner(System.in);

    int[] arr = new int[5];

    for (int i = 0; i < 5; i++) {
      arr[i] = sc.nextInt();
    }

    int k = sc.nextInt();
    
    String result = "Yay!";

    loop: for (int i = 0; i < 5; i++) {
      for (int j = i + 1; j < 5; j++) {
        if (k < (arr[j] - arr[i])) {
          result = ":(";
          break loop;
        }
      }
    }

    System.out.println(result);

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

    Scanner sc = new Scanner(System.in);

    int[] arr = new int[5];

    for (int i = 0; i < 5; i++) {
      arr[i] = sc.nextInt();
    }

    int k = sc.nextInt();
    
    String result = "Yay!";

    loop: for (int i = 0; i < 5; i++) {
      for (int j = i + 1; j < 5; j++) {
        if (k < (arr[j] - arr[i])) {
          result = ":(";
          break loop;
        }
      }
    }

    System.out.println(result);

  }
} Main
import java.util.*;
public class Main {
  public static void main(String[] args){

    Scanner sc = new Scanner(System.in);

    int[] arr = new int[5];

    for (int i = 0; i < 5; i++) {
      arr[i] = sc.nextInt();
    }

    int k = sc.nextInt();
    
    String result = "Yay!";

    loop: for (int i = 0; i < 5; i++) {
      for (int j = i + 1; j < 5; j++) {
        if (k < (arr[j] - arr[i])) {
          result = ":(";
          break loop;
        }
      }
    }

    System.out.println(result);

  }
}