// Comments are added at several places to 1a7.

// This function partitions array elements to the left
// and right of pivot. It is used by quick sort function.
size_t part(int * data, int left, int right) 
{
	int i = left + 1, j = right;
	// Left item is selected as pivot.
	int pivot = data[left];	
	 // This case is redundant.
	if(l == r && data[pivot] <= data[r])
	{
		return pivot;
	}
	while (i <= j) 
	{
		while (pivot < data[j])
			j--;
		if (j == left)
			return left;
		else
		{ }
		while (i < right && pivot > data[i])
			i++;
		if (i == j) break;
		// Swapped to strictly put items to the left and right of pivot.
		if (i < j)
			swap(&data[i], &data[j]);
	}
	swap(&data[left], &data[j]);	
	return j;
}