System.Collections.ArrayList.ArrayListAdapter.QuickSort C# (CSharp) Method

			internal static void QuickSort(IList list, int left, int right, IComparer comparer) 
			{
				int i, j, middle;
				object pivot;
					
				if (left >= right) 
				{
					return;
				}

				// Pick the pivot using the median-of-three strategy.

				// Be careful with overflows
				middle = left + ((right - left) / 2);

				if (comparer.Compare(list[middle], list[left]) < 0) 
				{
					Swap(list, middle, left);
				}

				if (comparer.Compare(list[right], list[left]) < 0) 
				{
					Swap(list, right, left);
				}

				if (comparer.Compare(list[right], list[middle]) < 0) 
				{
					Swap(list, right, middle);
				}
		
				if (right - left + 1 <= 3) 
				{
					return;
				}
		
				// Put the pivot in right - 1.
				Swap(list, right - 1, middle);

				// List should look like:
				//
				// [Small] ..Numbers.. [Middle] ..Numbers.. [Pivot][Large]

				pivot = list[right - 1];

				// Sort from (left + 1) to (right - 2).

				i = left;
				j = right - 1;			
		
				for (;;) 
				{
					while (comparer.Compare(list[++i], pivot) < 0);
					while (comparer.Compare(list[--j], pivot) > 0);
			
					if (i < j) 
					{
						Swap(list, i, j);
					}
					else 
					{
						break;
					}
				}

				// Put pivot into the right position (real middle).

				Swap(list, right - 1, i);

				// Recursively sort the left and right sub lists.

				QuickSort(list, left, i - 1, comparer);
				QuickSort(list, i + 1, right, comparer);		
			}