#4ExtractAllUniqueWords

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

public class ExtractAllUniqueWords {

    public static void main(String[] args) {

        Scanner scan = new Scanner(System.in);
        String input = scan.nextLine();
        String[] splittedInput = input.split("\\W+");
        TreeSet<String> uniqueWords = new TreeSet<>(String.CASE_INSENSITIVE_ORDER);

        for (String word : splittedInput) {
            uniqueWords.add(word);
        }

        for (String word : uniqueWords) {
            System.out.print(word.replaceAll("\\W+", "").toLowerCase() + " ");
        }
    }
}