import java.util.Scanner;
import java.util.TreeSet;

public class ExtractAllUniqueWords {

    public static void main(String[] args) {
        try (Scanner scanner = new Scanner(System.in)) {
            String[] words = scanner.nextLine().split("\\W+");
            TreeSet<String> orderedWords = new TreeSet<>();
            for (int i = 0; i < words.length; i++) {
                orderedWords.add(words[i].toLowerCase());
            }
            // print
            for (String word : orderedWords) {
                System.out.print(word + " ");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}