using System;
using System.Linq;
using System.Collections.Generic;

namespace Algorithm
{
    class Program
    {
        static void Main(string[] args)
        {
            var X = Console.ReadLine().ToCharArray().OrderByDescending(z => z).ToArray();
            var prev = new char[X.Length];
            Array.Copy(X, prev, X.Length);

            var first = true;
            do
            {
                if (first) first = false;
                else
                {
                    var s = new string(X);
                    if (s[0] == '0') break;
                    if (new string(prev) != s)
                    {
                        Console.WriteLine(s);
                        return;
                    }
                }
            } while (PrevPermutation(X));

            Console.WriteLine(-1);
        }

        public static bool PrevPermutation<T>(T[] array, int index, int length, Comparison<T> comp)
        {
            if (length <= 1) return false;
            for (int i = length - 1; i > 0; i--)
            {
                int k = i - 1;
                if (comp(array[k], array[i]) > 0)
                {
                    int j = Array.FindLastIndex(array, delegate (T x) { return comp(array[k], x) > 0; });
                    Swap(ref array[k], ref array[j]);
                    Array.Reverse(array, i, length - i);
                    return true;
                }
            }
            Array.Reverse(array, index, length);
            return false;
        }

        public static bool PrevPermutation<T>(T[] array) where T : IComparable
        {
            return PrevPermutation(array, 0, array.Length, Comparer<T>.Default.Compare);
        }

        public static void Swap<T>(ref T one, ref T two)
        {
            var temp = one;
            one = two;
            two = temp;
        }
    }
}