/// <summary>
/// 堆排序(nlgn)
/// </summary>
/// <returns></returns>
public int[] HeapSort()
{
for (int i = _array.Length - 1; i > 0; i--)
{
SortUtil.Swap(args: _array, 0, i);
HeapSize--;
MaintainHeap(0);
}
return(_array);
}
/// <summary>
/// 维护堆的性质
/// </summary>
/// <param name="i"></param>
public void MaintainHeap(int i)
{
int l = Left(i);
int r = Right(i);
int min = i;
if (l < HeapSize && _array[l] < _array[min])
{
min = l;
}
if (r < HeapSize && _array[r] < _array[min])
{
min = r;
}
if (min != i)
{
SortUtil.Swap(_array, i, min);
MaintainHeap(min);
}
}