public static ArrayList<Integer> duplicates(int arr[], int n) {

HashMap<Integer, Integer> freqMap = new HashMap<>();

ArrayList <Integer> dupes = new ArrayList<>();

for (int element : arr) {

freqMap.put(element, freqMap.getOrDefault(element, 0) + 1);

}

for (int element : freqMap.keySet()) {

if (freqMap.get(element) > 1) {

dupes.add(element);

}

}

if (dupes.size() == 0) {

dupes.add(-1);

}

Collections.sort(dupes);

return dupes;

}

public static void main(String[] args) {

// int arr[] = {0, 3, 1, 2};

// int n = 4;

// int arr[] = {2,3,1,2,3};

// int n = 5;

int arr[] = {13, 9, 25, 1, 1, 0, 22, 13, 22, 20, 3, 8, 11, 25, 10, 3, 15, 11, 19, 20, 2, 4, 25, 14, 23, 14};

int n = 26;

ArrayList<Integer> output = duplicates(arr, n);

System.out.println("Output: " + output); // Output:

}