#include <algorithm>
#include <vector>
#include <iterator>
#include <iostream>
#include <string>

int main()
{
    std::vector<std::pair<int, std::string>> words { };

    int index { 0 };
    std::transform(std::istream_iterator<std::string>{ std::cin },
                   std::istream_iterator<std::string>{ },
                   std::back_inserter(words),
                   [&index](std::string const& word) { return std::make_pair(index++, word); });

    std::sort(words.begin(), words.end(), [](auto const& a, auto const& b)
                                          { return a.second < b.second; });

    words.erase(std::unique(words.begin(), words.end(),
                            [](auto const& a, auto const& b) { return a.second == b.second; }),
                words.end());

    std::sort(words.begin(), words.end());

    std::transform(words.begin(), words.end(),
                   std::ostream_iterator<std::string>{ std::cout, " " },
                   [](auto const& p) { return p.second; });
    
    std::cout << std::endl;
}