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

std::string to_lower(std::string const& s) {
    std::string result;
    std::transform(s.begin(), s.end(), std::back_inserter(result), ::tolower);
    return result;
}

int main() {
    std::vector<std::string> suggestions {
        std::istream_iterator<std::string>{ std::cin },
        std::istream_iterator<std::string>{ }
    };

    std::transform(suggestions.begin(), suggestions.end(), suggestions.begin(), to_lower);

    std::sort(suggestions.begin(), suggestions.end());
    suggestions.erase(std::unique(suggestions.begin(), suggestions.end()), suggestions.end());

    std::sort(suggestions.begin(), suggestions.end(), [](std::string const& a, std::string const& b) {
        if (a.size() != b.size()){
          return a.size() < b.size();  
        } 
        return a < b;
    });

    auto  half = suggestions.size() / 2;
    std::copy(suggestions.begin(), suggestions.begin() + half,
              std::ostream_iterator<std::string>(std::cout, " "));
    std::cout << std::endl;

    return 0;
}