#include <iostream>
#include <iterator>
#include <set>
using namespace std;

int main() {
	using data_type = int;
	set<data_type> data_set;
	
	//change cin to your ifstream
	copy(istream_iterator<data_type>(cin), 
	     istream_iterator<data_type>(), 
	     inserter(data_set, end(data_set)));
	
	//change cout to your ofstream
	copy(begin(data_set), end(data_set), ostream_iterator<data_type>(cout, " "));
	
	return 0;
}