缘由如何用C＋＋解决一下问题_编程语言-CSDN问答

	int a[]{1, 4, 7, 8, 5, 2, 3, 6, 9, 7}, n = 10, x = n, jh = 0, j = 0;

px:if (j < n)
{//缘由https://ask.csdn.net/questions/8099444
	if (--x < 2 + j)
		x = n - 1, j += 3;
	if (x < n - 1 && a[x + 1] > a[x - 2])
		jh = a[x + 1], a[x + 1] = a[x - 2], a[x - 2] = jh;
	if (a[x] > a[x - 2])jh = a[x], a[x] = a[x - 2], a[x - 2] = jh;
	if (a[x] > a[x - 1])jh = a[x], a[x] = a[x - 1], a[x - 1] = jh;
	if (a[x - 1] > a[x - 2])jh = a[x - 1], a[x - 1] = a[x - 2], a[x - 2] = jh;
	goto px;
}

	int a[]{1, 4, 7, 8, 5, 2, 3, 6, 9, 7}, n = 10, x = n, jh = 0;
//获取第三大的数,小于O(N)的自创算法.
px:if (x-- > 2)
{
	if (x < n - 1 && a[x + 1] > a[x - 2])
		jh = a[x + 1], a[x + 1] = a[x - 2], a[x - 2] = jh;
	if (a[x] > a[x - 2])jh = a[x], a[x] = a[x - 2], a[x - 2] = jh;
	if (a[x] > a[x - 1])jh = a[x], a[x] = a[x - 1], a[x - 1] = jh;
	if (a[x - 1] > a[x - 2])jh = a[x - 1], a[x - 1] = a[x - 2], a[x - 2] = jh;
	goto px;
}

void 新三个数排序的自创算法()
{
	int a[]{1, 4, 7, 8, 5, 2, 3, 6, 9, 7}, n = 10, x = n, jh = 0, j = 0, s = 0;

px:if (j < n)
{//缘由https://ask.csdn.net/questions/8099444
	if (--x < 2 + j)
		x = n - 1, j += 3;
	if (x < n - 1 && a[x + 1] < a[x - 2])
		jh = a[x + 1], a[x + 1] = a[x - 2], a[x - 2] = jh;
	if (a[x] < a[x - 2])jh = a[x], a[x] = a[x - 2], a[x - 2] = jh;
	if (a[x] < a[x - 1])jh = a[x], a[x] = a[x - 1], a[x - 1] = jh;
	if (a[x - 1] < a[x - 2])jh = a[x - 1], a[x - 1] = a[x - 2], a[x - 2] = jh;
	++s;
	goto px;
}cout << s << "\n";
}

这是我厉年来很满意的一次排序算法设计，最好小于O（N）最坏O（（NN/3）/2），若再写成双向效率更高，再写为递归速度更快。