void 按升序输出三个数()
{//缘由https://ask.csdn.net/questions/7638568?spm=1005.2025.3001.5141
	int a = 0, b = 0, c = 0;
	scanf_s("%d%d%d", &a, &b, &c);
	if (a > c)算交换(a, c);
	if (a > b)算交换(a, b);
	if (b > c)算交换(b, c);
	printf("%d->%d->%d", a, b, c);
}