Exercise 2D Array With Counting

import java.util.Arrays;
import java.util.Random;

public class FacebookSolution2 {

    public static void main(String[] args) {

        int[][] arr = new int[10][10];
        Random random = new Random();

        for (int i = 0; i < arr.length; i++) {
            for (int j = 0; j < arr[i].length; j++) {
                arr[i][j] = random.nextInt(10) + 1;
            }
        }

        for (int i = 0; i < arr.length; i++) {
            System.out.println(Arrays.toString(arr[i]));
        }

        System.out.println(countNumbers(arr));
    }

    static int countNumbers(int[][] arr){
        int maxNumber = arr[0][0];

        for (int i = 0; i < arr.length ; i++) {
            for (int j = 0; j < arr[i].length; j++) {
                if (maxNumber < arr[i][j]){
                    maxNumber = arr[i][j];
                }
            }
        }

        int[] helper = new int[maxNumber +1];

        for (int i = 0; i < arr.length ; i++) {
            for (int j = 0; j < arr[i].length; j++) {
                helper[arr[i][j]]++;
            }
        }


        int maxIndex = helper[0];
        int number = 0;

        for (int i = 0; i < helper.length; i++) {
            if (helper[i] > maxIndex){
                maxIndex = helper[i];
                number = i;
            }
        }
        return  number;

    }
}