Write a program to print the repeated values from an Integer Array in an Ascending order

Write a program to print the repeated values from an Integer Array in an Ascending order

WAP to print the repeated values in an Ascending order From the Integer Array  

The below program is to print the repeated values from an Integer array in Ascending order is asked in many interviews,print the repeated values from an integer array in an ascending order please find the below program 

package com.st.List;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.*;

public class SortingTest {
    public static void main(String[] args) {
        System.out.println("Hello World!");
        int a[] = { 2, 2, 2, 1, 4, 4, 3, 3, 3, 1, 9, 9, 1, 5, 7, 8 };
        TreeSet<Integer> s = new TreeSet<Integer>();
        int c = 0, i = 0, j = 0;
        for (i = 0; i < a.length; i++) {
            c = 0;
            for (j = 0; j < a.length; j++) {
                if (a[i] == a[j]) {
                    c++;
                }
            }
            if (c > 1) {
                s.add(a[i]);
            }
        }
        Iterator it = s.iterator();
        while (it.hasNext()) {
            System.out.print(it.next() + " ");
        }

    }
}