gistfile1.txt

import java.util.*;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int[] array = new int[n];
        Map<Integer, Integer> map = new HashMap<>();
        for (int i = 0; i < n; ++i) {
            int a = scanner.nextInt();
            array[i] = a;
            map.put(a, i);
        }
        List<Integer> result = new ArrayList<>();
        for (int i = 0; i < n; ++i) {
            int element = array[i];
            if (map.get(element) != i) {
                result.add(element);
            }
        }
        System.out.println(result.size());
        System.out.println(joinToString(result));
    }

    private static <T> String joinToString(Iterable<T> iterable) {
        StringBuilder sb = new StringBuilder();
        for (T item : iterable) {
            sb.append(item.toString());
            sb.append(" ");
        }

        if (sb.length() > 0) {
            sb.deleteCharAt(sb.length() - 1);
        }

        return sb.toString();
    }
}