剑指offer——面试题11：快速排序

#include"iostream"
#include"random"
using namespace std;

/*
void Swap(int &a,int &b)
{
    int tmp;
    tmp=a;
    a=b;
    b=tmp;
}
*/
//官方给的partition函数
int Partition1(int *data,int start,int end)
{
    int index=start+(rand()%(end-start+1));
    swap(data[index],data[end]);
    int small=start-1;
    for(index=start;index<end;index++)
    {
        if(data[index]<data[end])
        {
            small++;
            if(index!=small)
                swap(data[index],data[small]);
        }
    }
    small++;
    swap(data[small],data[end]);
    return small;
}

//自定义Partition函数
int Partition2(int *data,int start,int end)
{
    int value=data[start];
    while(start<end)
    {
        while(start<end)
        {
            if(data[end]>value)
                end--;
            else
                break;
        }
        if(start<end)
            data[start++]=data[end];
        while(start<end)
        {
            if(data[start]<=value)
                start++;
            else
                break;
        }
        if(start<end)
            data[end--]=data[start];
    }
    data[start]=value;
    return start;
}

void QuickSort1(int *data,int start,int end)
{
    if(start==end) return;

    int mid=Partition1(data,start,end);
    if(mid>start)
        QuickSort1(data,start,mid-1);
    if(mid<end)
        QuickSort1(data,mid+1,end);
}

void QuickSort2(int *data,int start,int end)
{
    if(start==end) return;

    int mid=Partition2(data,start,end);
    if(mid>start)
        QuickSort2(data,start,mid-1);
    if(mid<end)
        QuickSort2(data,mid+1,end);
}

#include"QuickSort.h"

void Test1()
{
    int data[10]={6,4,1,5,2,9,8,10,3,7};
    cout<<"use QuickSort1:";
    QuickSort1(data,0,9);
    for(int i=0;i<10;i++)
        cout<<data[i]<<" ";
    cout<<endl;
}

void Test2()
{
    int data[10]={6,4,1,5,2,9,8,10,3,7};
    cout<<"use QuickSort2:";
    QuickSort2(data,0,9);
    for(int i=0;i<10;i++)
        cout<<data[i]<<" ";
    cout<<endl;
}
int main()
{
    Test1();
    Test2();
}