剑指offer 高速排序

高速排序一般的写法。教科书上非常具体，这里介绍作者的写法。

程序例如以下：

#include<iostream>
#include<stack>
using namespace std;
void swap(int *value1, int *value2)
{
    int temp = *value1;
    *value1 = *value2;
    *value2 = temp;
}

int partition(int data[],int length,int start,int end)
{
    if (NULL == data || length <= 0 || start < 0 || end >= length)
        throw exception("Invalid Data!");
    int small = start - 1;
    for (int index = start; index < end; index++)
    {
        if (data[index] <= data[end])
        {
            small++;
            if (small != index)
                swap(&data[index],&data[small]);
        }
    }
    small++;
    swap(&data[small],&data[end]);
    return small;
}

void QuickSort(int data[], int length, int start, int end)
{
    if (start == end)
        return;
    int index = partition(data,length,start,end);
    if (start < index)
        QuickSort(data, length, start, index-1);
    if (index < end)
        QuickSort(data, length, index+1, end);
}

int main()
{
    int data[] = {5,7,2,4,9,3,8,4,1};
    QuickSort(data,9,0,8);
    for (int i = 0; i < 9; i++)
    {
        cout << i << " ";
    }
    return 0;
}