堆排Heap Sort

1.

#define LeftChild(i) (2*(i)+1)
void PercDown(vector<int>&num, int i, int n)
{
	int child;
	int tmp;
	for (tmp = num[i]; LeftChild(i) < n; i = child)
	{
		child = LeftChild(i);
		if (child != n - 1 && num[child + 1] > num[child])
			child++;
		if (tmp < num[child])
			num[i] = num[child];
		else
			break;
	}
	num[i] = tmp;
}
for (int i = n - 1; i>0; i--)
	{//进行堆排
		swap(numCopy[0], numCopy[i]);
		PercDown(numCopy, 0, i);
}