using System;

public class Program

{

    public static void Main()

    {

        string zzz="mot nguoi x Hai khong n 999 tuoi";

        string xyz = upperCaseFirstLetterButExceptOneChar(zzz);

        Console.WriteLine(xyz);

    }

    public static string upperCaseFirstLetterButExceptOneChar(string input)

    {

        string[] words = input.Split(' ');

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

        {

            if(words[i].Length >1)

            {

                words[i]=char.ToUpper((words[i])[0])+words[i].Substring(1);

            }

        }

        return string.Join(" ", words);

    }

}