using System.Linq;
using System;

public class Hello
{
    static void Main()
    {
        var s = Console.ReadLine().Trim().ToArray();
        Console.WriteLine(getAns(s));
    }
    static string getAns(char[] s)
    {
        Array.Sort(s);
        for (int i = 0; i < s.Length - 1; i++)
        {
            if (s[i] != s[i + 1])
            {
                var tmp = s[i];
                s[i] = s[i + 1];
                s[i + 1] = tmp;
                if (s[s.Length - 1] != '0')
                {
                    Array.Reverse(s);
                    var ans = new string(s);
                    return ans;
                }
                else return "-1";
            }
        }
        return "-1";
    }
}