import java.util.Scanner;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
     public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        int n= scanner.nextInt();
        System.out.println(getUniqueDigits(n));
    }
    public static int getUniqueDigits(int n){
        Set<Integer> seen=new HashSet<>();
        int result=0;
        while(n>0){
            int digit=n%10;
            if(!seen.contains(digit)){
                seen.add(digit);
                result =result*10+digit;
            }
            n/=10;
        }
        return result;
    }
}