import java.util.*;

public class Main{
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        while(sc.hasNext()){
            int num = sc.nextInt();
            HashSet<Integer> sh = new HashSet<Integer>();
            while(num!=0){
                int temp = num%10;
                if(sh.add(temp)){
                    System.out.print(temp);
                }
                num = num/10;
            }
            System.out.println();
        }
    }
}