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();
}
}
}