using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {   

        string input = "have a nice day";

        //Expected Output: "aaac d eehi nvy";

        string output = SortString(input);

        Console.WriteLine(output);

    }

    public static string SortString(string input)

    {

        string output = "";

        string  stringPos = input.Split(',' );

        Char[] arry  = input.ToCharArray();

        Array.Sort(arry);//sorted array

        for(int i =0; i <= arry.Length-1; i++)

        {

            output+= arry[i];

        }

        return output;

    }

}