using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.IO;
namespace Pb10
{
    class Program
    {
        static object countLock = new object();
        private const string FILE_NAME="suma.txt";
        static void Main(string[] args)
        {
            using (File.Create(FILE_NAME));
            int[] array = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };
            while (array.Length / 2 >= 1)
            {
                int[] aux;
                //daca dimensiunea este impara adaugam un 0 la sfarsit
                if (array.Length % 2 != 0)
                {
                    aux = array;
                    array = new int[aux.Length + 1];
                    for (int i = 0; i < aux.Length; i++)
                    {
                        array[i] = aux[i];
                    }
                    array[aux.Length] = 0;
                }

                for (int i = 0; i < array.Length / 2; i++)
                {
                    Thread t = new Thread(delegate()
                        {
                            int c = array[i * 2] + array[i * 2 + 1];
                            string lines = c + " ";
                            array[i] = c;
                            //folosit pentru accesul concurent la obiecte
                            Monitor.Enter(countLock);
                            //using se asigura ca Dispose este apelata chiar daca se arunca o exceptie asupra metodelor din obiect
                            using (System.IO.StreamWriter file = File.AppendText(FILE_NAME))
                            {
                                file.WriteLine(lines);
                            }
                            Monitor.Exit(countLock);
                        });
                    t.Start();
                    t.Join();
                }
                aux = array;
                array = new int[array.Length / 2];
                for (int i = 0; i < array.Length; i++)
                {
                    array[i] = aux[i];
                }
            }
        }
    }
}