using System;

using System.Text;

public class Program

{

    public static void Main()

    {

        StringBuilder builder = new StringBuilder();

        int input = 123987654;

        string firstdigit = input.ToString().Substring(0,1);

        builder.Append(firstdigit);

        string allExceptFirstDigit = input.ToString().Remove(0,1).ToString(); // 82

        //Console.WriteLine("all except first digit" + allExceptFirstDigit);

        //Split 82 into integer array and sort and then concat

         char[] integers = allExceptFirstDigit.ToCharArray();

        int[] intArray  = new int[integers.Length];

         for(int i = 0 ; i< integers.Length ; i ++)

         {

            intArray[i] = Convert.ToInt32(integers[i].ToString());

         }

        //Sort

        Array.Sort(intArray);

        //Array.Reverse(intArray);

        //Concat

        foreach(var i in intArray)

        {

          builder.Append(i);

        }

        //Print

        Console.WriteLine(String.Format("Given number : {0} , Next smallest number:{1}",input , Convert.ToInt32(builder.ToString())));

    }

}