I'm Developing a Code for java to Fold the element inside an array with example

**A[0] = 2**, **A[1] = 7**, **A[2] = 9**, **A[3] = 7**

Then Fold it with this format

**A[0] = (A[0] + A[3]) mod 10 = 9**

**A[1] = (A[1] + A[2]) mod 10 = 6**

And Fold it again until single

**A[0] = (A[0] + A[1]) mod 10 = 5**

Below are incomplete code:

```java
import java.util.ArrayList;
import java.util.List;
import java.lang.Math;

public class ArrayFolder {

    public static void main(String[] args) {

        //ArrayList
        int[] A = {
            2,
            7,
            9,
            7
        };

        //To define a new Array later
        List<Integer> intList = new ArrayList<Integer>();

        //To print the ArrayList A
        for (int x = 0; x < A.length; x++) {
            System.out.println("A[" + x + "]= " + A[x]);
        }

        //Function to fold the ArrayList into half
        int res = 0;
        int result = 0;

        //if A.length is Even
        if (A.length % 2 == 0) {
            for (int i = 0; i < A.length / 2; i++) {
                res = A[i] + A[A.length - 1 - i];
                result = res % 10;
                intList.add(result);
            }
        }

        //if A.length is Odd
        else {
            for (int i = 0; i < A.length / 2; i++) {
                res = A[i] + A[A.length - 1 - i];
                result = res % 10;
                intList.add(result);
            }
            result = A[A.length / 2];
            intList.add(result);
        }

        //add the int to New ArrayList
        Integer[] intArray = new Integer[intList.size()];
        intArray = intList.toArray(intArray);
        System.out.println("\nNew Array ");

        for (Integer s: intArray) {
            System.out.println(s);
        }

    }
}

```

Compiled result

```
A[0]= 2
A[1]= 7
A[2]= 9
A[3]= 7

New Array
9
6

```

I couldn't find an efficient way to keep looping the function, so the code will stop folding when a single Integer achieved.

My question is, is there any efficient way to loop the process so later It can work with a larger element of Array?.

Kindly provide the logic or the code so I can continue with my code.

Many Thanks