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

class Main
{
    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
        char[] cs = sc.next().toCharArray();
        int[] a = new int[cs.length];
        int cnt0 = 0;
        for (int i = 0; i < a.length; ++i) {
            a[i] = (int) (cs[i] - '0');
            if (a[i] == 0) ++cnt0;
        }
        Arrays.sort(a);
        boolean same = true;
        for (int i = 0; i < a.length; ++i) same &= a[i] == a[0];
        if (same || cnt0 == a.length - 1) {
            System.out.println(-1);
            return;
        }
        int p = 0;
        while (a[p] == a[p + 1]) ++p;
        a[p + 1] ^= a[p];
        a[p] ^= a[p + 1];
        a[p + 1] ^= a[p];
        PrintWriter pw = new PrintWriter(System.out);
        for (int i = a.length - 1; i >= 0; --i) {
            pw.print(a[i]);
        }
        pw.println();
        pw.close();
    }
}