private static int Partition <T>(this T[] list, int startIndex, int endIndex, int pivotIndex, IComparer <T> comparer, QuickselectSortOrder order)
{
Swap(list, pivotIndex, startIndex);
var pivot = list[startIndex];
var i = startIndex;
var j = endIndex + 1;
while (true)
{
do
{
i++;
} while (i <= endIndex && comparer.CompareWithOrder(list[i], pivot, order) < 0);
do
{
j--;
} while (comparer.CompareWithOrder(list[j], pivot, order) > 0);
if (i >= j)
{
Swap(list, startIndex, j);
return(j);
}
Swap(list, i, j);
}
}
private static int IndexOfMin <T>(this T[] list, IComparer <T> comparer, QuickselectSortOrder order)
{
var minIndex = 0;
for (var i = 0; i < list.Length; i++)
{
if (comparer.CompareWithOrder(list[i], list[minIndex], order) < 0)
{
minIndex = i;
}
}
return(minIndex);
}