using System;
using System.Collections.Generic;
using System.Text;

class Program
{
    public void Proc()
    {
        Reader.IsDebug = false;
        string num = Reader.ReadLine();
        List<char> sorted = new List<char>();
        sorted.AddRange(num.ToCharArray());
        sorted.Sort();
        sorted.Reverse();

        int idxFrom = -1;
        int idxTo = -1;
        for (int i = 0; i < sorted.Count - 1; i++)
        {
            if (num[i] != sorted[i])
            {
                idxFrom = i;
                char findFor = sorted[i];
                idxTo = num.LastIndexOf(findFor);
                break;
            }
        }
        char[] arr = num.ToCharArray();
        if (idxFrom >= 0)
        {
            char tmp = arr[idxFrom];
            arr[idxFrom] = arr[idxTo];
            arr[idxTo] = tmp;
        }
        StringBuilder ans = new StringBuilder();
        foreach (char c in arr)
        {
            ans.Append(c);
        }
        Console.WriteLine(ans.ToString());
    }


    public class Reader
    {
        public static bool IsDebug = true;
        private static String PlainInput = @"


999999999






 
";
        private static System.IO.StringReader Sr = null;
        public static string ReadLine()
        {
            if (IsDebug)
            {
                if (Sr == null)
                {
                    Sr = new System.IO.StringReader(PlainInput.Trim());
                }
                return Sr.ReadLine();
            }
            else
            {
                return Console.ReadLine();
            }
        }
        public static int[] GetInt(char delimiter = ' ', bool trim = false)
        {
            string inptStr = ReadLine();
            if (trim)
            {
                inptStr = inptStr.Trim();
            }
            string[] inpt = inptStr.Split(delimiter);
            int[] ret = new int[inpt.Length];
            for (int i = 0; i < inpt.Length; i++)
            {
                ret[i] = int.Parse(inpt[i]);
            }
            return ret;
        }
    }
    static void Main()
    {
        Program prg = new Program();
        prg.Proc();
    }
}