import java.util.LinkedHashSet; import java.util.Scanner; import java.util.Set; public class e3 { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); while (scanner.hasNext()) { String str = scanner.nextLine(); Set<Character> set = new LinkedHashSet<>(); for (int i = 0; i < str.length(); i++) { Character c = str.charAt(i); { if (!set.contains(c)) { System.out.print(c); set.add(c); } } } System.out.println(); } } }