What am I doing wrong?

Question about the task

Is anyone there?

Java Syntax, Level 6, Lesson 8

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It's a simple task and my solution works fine in the IDE.

Implement the main(String[]) method, which displays true if the element is contained in the passed array, otherwise false.
The array variable should not change the position of its elements.

To search for an element in an array, you need a binary search. To do this, use the static Arrays.binarySearch(int[], int) method of the Arrays class.
In the first argument, pass a sorted array to be searched. The second parameter is the element to be searched for.
The Arrays.binarySearch(int[], int) method returns the index of the query element, if such an element exists in the array.

You can use the Arrays.sort(int[]) method to sort the array.
During testing, the values of the variables in the Solution class will be different.

Requirements:

In the main(String[]) method, do not change the position of the elements in the array.
When the main(String[]) method is called, display true if the value of the element variable is contained in the array.
When the main(String[]) method is called, display false if the passed element is not contained in the array.
In the main(String[]) method, use a call to the Arrays.binarySearch(int[], int) method.

package en.codegym.task.pro.task05.task0519; import java.util.Arrays; /* Is anyone there? */ public class Solution { public static int[] array = {9, 8, 7, 6, 5, 4, 3, 2, 1}; public static int element = 5; public static void main(String[] args) { System.out.println(Arrays.binarySearch(array, element) > 0); } }

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Gellert Varga

Level 23 , Szekesfehervar, Hungary

26 September 2021, 21:21

Hi PeterC! "I've chosen the AP Exam path" - but what is it? I have not come across such an option either. And I don't have such a task listed - it's blocked for me, like when I haven't reached a certain level.

PeterC Android Developer

27 September 2021, 17:26

Hi, Gellert. Have you chosen it during the creation of your account? Check the list of lessons in the first quest. It should be 18. The typical path has only 10 - it's faster but I remember it was being to difficult, compressed and frustrating. The AP Exam is absolutely great and should be the typical path, rather an option. Also, I love your avatar.

Thomas

Level 41 , Bayreuth, Germany

25 September 2021, 14:31

useful

binarySearch requires a sorted array. And sorting is suggested by the requirements anyway.

PeterC Android Developer

25 September 2021, 14:49

Certainly, but if I put

Arrays.sort(array);

before the println, the first two conditions are not accepted, namely: In the main(String[]) method, do not change the position of the elements in the array. When the main(String[]) method is called, display true if the value of the element variable is contained in the array.

PeterC Android Developer

25 September 2021, 14:56

OK, I see it now. We're supposed to copy it to a new array and then sort it. Thank you, Thomas.

Thomas

Level 41 , Bayreuth, Germany

25 September 2021, 15:04

perfect ;) btw. does that pro in the package mean that this is some additional task only available in the premium pro subscription?

PeterC Android Developer

25 September 2021, 15:18

I've chosen the AP Exam path. It's slightly different from the regular one. I was able to compare both paths and the passage in the first chapter is different (i.e. 18 level in the first quest). And I must say I like it more - the passage of tasks and topic makes more sense to me. I did the regular path a couple of years ago and I remember struggling with many tasks that seemed to be out of place (i.e. basic topics had tasks requiring knowledge waaay beyond that topic). I think it's still in the making but I like it much more. Disadvantage is that upon clicking Community Help for any task you find empty lists, no answers, no opportunity for comparing solutions with the community. So, I'm thankful for your willingness to help.

Thomas

Level 41 , Bayreuth, Germany

25 September 2021, 16:14

Ahh, OK, thanks for the info... really interesting. But I can not remember beeing offered such a path... now it is to late anyways. But if you ask questions frequently I'm able to do the tasks, too.