Сортировка слиянием

static Int32[] Merge_Sort(Int32[] massive)
{
  if (massive.Length == 1)
    return massive;
  Int32 mid_point = massive.Length / 2;
  return Merge(Merge_Sort(massive.Take(mid_point).ToArray()), Merge_Sort(massive.Skip(mid_point).ToArray()));
}
 
static Int32[] Merge(Int32[] mass1, Int32[] mass2)
{
  Int32 a = 0, b = 0;
  Int32[] merged = new int[mass1.Length + mass2.Length];
  for (Int32 i = 0; i < mass1.Length + mass2.Length; i++)
  {
    if (b < mass2.Length && a < mass1.Length)
      if (mass1[a] > mass2[b])
      merged[i] = mass2[b++];
      else //if int go for
      merged[i] = mass1[a++];
    else
      if (b < mass2.Length)
      merged[i] = mass2[b++];
      else
      merged[i] = mass1[a++];
  }
  return merged;
}
 
static void Main(string[] args)
{
  Int32[] arr = new Int32[100];
 
  //заполняем массив случайными числами
  Random rd = new Random();
  for(Int32 i = 0; i < arr.Length; ++i) {
    arr[i] = rd.Next(1, 101);
  }
  
  System.Console.WriteLine("The array before sorting:");
  foreach (Int32 x in arr)
    System.Console.Write(x + " ");
 
  //сортировка
  arr = Merge_Sort(arr);
 
  System.Console.WriteLine("\n\nThe array after sorting:");
  foreach (Int32 x in arr)
    System.Console.Write(x + " ");
 
  System.Console.WriteLine("\n\nPress the <Enter> key");
  System.Console.ReadLine();
}

return Merge(Merge_Sort(massive.Take(mid_point).ToArray()), Merge_Sort(massive.Skip(mid_point).ToArray()));