排序算法-快速排序

#include<stdlib.h>    
#include<stdio.h>    


using namespace std;


void swap(int* arry,int low,int high)
{
int tmp = arry[low];
arry[low] = arry[high];
arry[high] = tmp;
}


int partition(int* arry,int low,int high)
{
int pv = arry[low];
while (low<high)
{
while (low<high&&arry[high]>=pv)
{
high--;//比基準大，本來就在右邊，所以high前移動
}
swap(arry,low,high);
while (low<high&&arry[low]<=pv)
{
low++;
}
swap(arry,low,high);
}
//返回樞軸的位置    。。重要
return low;
}
void QSort(int* arry,int low,int high)
{
if (low<high)
{
//選一個pv值，把數據分別放在pv值的左右兩邊，並把pivot位置返回出來
int pivot = partition(arry,low,high);
//對子序列1排序
QSort(arry,low,pivot-1);
//對子序列2排序
QSort(arry,pivot+1,high);
}
}


void Quick_Sort(int * arry ,int count)
{
QSort(arry,0,count-1);
}




void main()
{
int arry[] = { 12,20,45,25,35,1,2,54,52 };
int count = sizeof(arry) / sizeof(*arry);
printf("arry數組個數：%d\n", count);
for (int i = 0; i < count; i++)
{
printf("%d ", arry[i]);
}
printf("\n排序之前");
Quick_Sort(arry, count);
for (int i = 0; i < count; i++)
{
printf("%d ", arry[i]);
}
printf("\n排序之後");
system("pause");
}