for (int i = index; i < max; i++)
                {
                    //parallel position
                    if (i < rangeEnd && i < addedCount - index)
                    {
                        T old = this[i],
                          @new = list[i - index];

                        if (comparer.Equals(old, @new))
                        {
                            OnRangeReplaced(i, newCluster, oldCluster);
                            continue;
                        }
                        else
                        {
                            Items[i] = @new;
                            newCluster.Add(@new);
                            oldCluster.Add(old);

                            changesMade = true;
                        }
                    }
                    else
                    {
                        OnRangeReplaced(i, newCluster, oldCluster);

                        //exceeding position
                        var items = (List<T>)Items;
                        if (rangeEnd > addedCount - index)
                        {
                            var removedCount = rangeEnd - addedCount;
                            T[] removed = new T[removedCount];
                            items.CopyTo(i, removed, 0, removed.Length);
                            items.RemoveRange(i, removedCount);
                            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, removed, i));
                        }
                        //new position
                        else
                        {
                            var k = i - index;
                            T[] added = new T[addedCount - k];
                            for (int j = k; j < addedCount; j++)
                            {
                                T @new = list[j];
                                added[j - k] = @new;
                            }
                            items.InsertRange(i, added);
                            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, added, i));
                        }
                        break;
                    }
                }