快速排序与二分查找

#include <iostream>
#include <string>
using namespace std;

void quicksort(int arry[], int low, int high)
{
    int oldlow = low;
    int oldhigh = high;

    if(low >= high)
    {
        return;
    }
    int key = arry[low];
    while(low < high)
    {
        while(low < high && arry[high] > key){ --high; };
        arry[low] = arry[high];

        while(low < high && arry[low] < key) { ++low; };
        arry[high] = arry[low];
    }
    arry[low] = key;
    quicksort(arry, oldlow, low - 1);
    quicksort(arry, high + 1, oldhigh);

}

bool binarysearch(int arry[], int n, int low, int high, int &key, int &index)
{
    if(low > n - 1 || high < 0 || low > high)
    {
        cout<<"can‘t find "<<key<<endl;
        return false;
    }
    int middle = (low + high) % 2 == 0 ? (low + high) / 2 : (low + high) / 2 + 1;
    if(arry[middle] == key)
    {
        index = middle;
        return true;
    }
    else
    {
        if(arry[middle] > key) high = middle - 1;
        if(arry[middle] < key) low = middle + 1;
    }

    return binarysearch(arry, n, low, high, key, index);
}

int main()
{
    int arry[] = {1,2,6,7,854,23,4,22,44,55};
    int size = sizeof(arry)/sizeof(arry[0]);
    quicksort(arry, 0, size -1);
    cout<<"arry size is "<<size<<", after sort is:"<<endl;
    for(int i = 0; i < size; ++i)
    {
        cout<<arry[i]<<",";
    }
    cout<<endl;
    cout<<"binarysearch test."<<endl;
    int index;
    int value = 854;
    if(binarysearch(arry, size, 0, size - 1, value, index))
    {
        cout<<"find "<<value<<" ok, index is "<<index<<endl;
    }
    value = 54;
    if(binarysearch(arry, size, 0, size - 1, value, index))
    {
        cout<<"find "<<value<<" ok, index is "<<index<<endl;
    }

    return 0;
}