// @nuget: Microsoft.SqlServer.Compact

// @nuget: Z.EntityFramework.Classic

// @nuget: Z.EntityFramework.Classic.SqlServerCompact

​

using System;

using System.Linq;

using System.Data.Entity;

​

//Create a method which can find the largest positive number using the same digits as the input, ignoring sign.

//Any numbers which exceed the maximum size for the output $type should be rounded down to the largest possible number. For example: 

//FindLargest(123)=321 

//FindLargest(989)=998 

//FindLargest(998)=998 

​

public class Program

{

    public static void Main()

    {

        string input = Console.ReadLine();

        Console.Write(FindLargest(input));

    }

    public static string FindLargest(string number)

    {

        string resultstring = "";

        char[] numberarray = number.ToCharArray();

        Array.Sort(numberarray);

        for(int i = (numberarray.Length - 1); i > -1;i--)

        {

            resultstring += numberarray[i];

        }

        return resultstring;    

    }

}