java

import java.util.*;
class Random {
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        int N;
        N = sc.nextInt();
        int []num = new int[N];
        for(int i=0;i < N;i++){
            num[i] = (int)(Math.random()*1000+1);
        }
        for(int i = 0;i < N-1;i++){
            for(int j = i+1;j < N;j++){
                int temp;
                if(num[i]>num[j]){
                    temp=num[i];
                    num[i]=num[j];
                    num[j]=temp;
                }
            }
        }
        int count = 0;
        for(int i = 0;i < N-1;i++){
            if(num[i] == num[i+1]){
                for(int j = i+1;j < N;j++){
                    num[j]=num[j+1];
                }
                count++;
            }
        }
        System.out.println((N-count));
        for(int i = 0;i < N-count;i++){
            System.out.printf(num[i]+" ");
        }
    }
}