郝斌说这就是快排（C实现）

9	5	8	10	2	3
↑low					↑high

可以取任意位置的值赋给val，这里取第一个位置的值9给val，val = 9；得

	5	8	10	2	3
↑low					↑high

 移动high，找一个比val小的值填补low位置，high =3<val=9,high的3赋给low 得

3	5	8	10	2
↑low					↑high

 此时high不动，移动low 找一个比val大的值赋给high，向右移动，当low值为10时

3	5	8	10	2
			↑low		↑high

 low=10>val=9 low的值10赋给high得

3	5	8		2	10
			↑low		↑high

 此时low不动，移动high，找一个比val小的值，high向左移动

3	5	8		2	10
			↑low	↑high

 high=2<val=9，high值2赋给low 得

3	5	8	2		10
			↑low	↑high

 high不动了，移动low,low向右移动，此时

3	5	8	2		10
				↑high ↑low

 low和high在同一位置，这就是val的位置，第一次排序只能得到val的位置，

3	5	8	2	9（val）	10
				↑low ↑high

重复此行为就是递归，最终就可以得到排序的结果，代码实现如下：

#include <stdio.h>
void Qsort(int* a, int low, int high);
int FindPos(int* a, int low, int high);
int main() 
{
	int a[6] = { 9,5,8,10,2,3 };
	int i;
	Qsort(a, 0, 5);
	for (i = 0; i < 6; ++i)
		printf("%d ", a[i]);
	printf("
");
	return 0;
}
void Qsort(int* a, int low, int high)
{
	int pos;
	if (low < high)
	{
		pos = FindPos(a, low, high);
		Qsort(a, low, pos - 1);
		Qsort(a, pos + 1, high);
	}
}
int FindPos(int* a, int low, int high)
{
	int val = a[low];
	while (low < high)
	{
		while (low < high && a[high] >= val)
			--high;
		a[low] = a[high];
		while (low < high && a[low] <= val)
			++low;
		a[high] = a[low];
	}
	a[low] = val;
	return low; //high == low;
	//return high; 
}