import java.io.*;
import java.util.*;

public class Main {
    static boolean exist = false;
    static int total = 0;
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        int[] counts = new int[10];
        for (char c : sc.next().toCharArray()) {
            counts[c - '0']++;
            total++;
        }
        make(0, counts, new char[total]);
        System.out.println(-1);
    }
    
    static void make(int idx, int[] counts, char[] str) {
        if (idx == total) {
            if (exist) {
                if (str[0] == '0') {
                    System.out.println(-1);
                } else {
                    System.out.println(str);
                }
                System.exit(0);
            } else {
                exist = true;
                return;
            }
        }
        for (int i = 9; i >= 0; i--) {
            if (counts[i] == 0) {
                continue;
            }
            counts[i]--;
            str[idx] = (char)(i + '0');
            make(idx + 1, counts, str);
            counts[i]++;
        }
    }
}
    
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    
}