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 = "";

        Char[] arrinput=input.ToCharArray();

        //Console.Write(arrinput.Length);

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

        {

            if(arrinput[i]!=' ')

            {

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

              {

                 var temp=arrinput[i];

​

                 if(arrinput[j+1]!=' ' && arrinput[i]>arrinput[j+1])

                 {

                   arrinput[i]=arrinput[j+1];

                    arrinput[j+1]=temp;

                 }

                else  if(arrinput[j+1]==' ' && arrinput[i]>arrinput[j+2]){

                  arrinput[i]=arrinput[j+2];

                    arrinput[j+2]=temp;

                }

              }

            }

            output=output+arrinput[i];

        }

        return output;

    }

}