#include <bits/stdc++.h> using namespace std; long long abc[11111111]; vector<long long> bcd; vector<long long> cde; set<long long>def; map<long long , long long>efg; int main() { long long a , b , c , d , e , f , g , h , i , j , k , l , m , n , o , p , q , r , s , t , u , v , w ,x , y , z ,cnt = 0, sum = 0, max , min , mun = 1; cin >> n; for(long long i = 0 ; i < n ; i++){ long long s; cin >> s; def.insert(s); } cout << n - def.size() << endl; for(long long s : def){ cout << s << " "; } return 0; }