二分法查找算法 （递归）

// 二分查找.cpp

#include "stdafx.h"
#include <string>

int search(int m[],int key,int low,int high)
{
int mid=(low+high)/2;
if (low>high)
return -1;
if (key==m[mid])
return mid;
else if (key<m[mid])
return search(m,key,low,mid-1);
else
return search(m,key,mid+1,high);
}

void main()
{
int a[]={1,2,5,7,9,12,16};
int i,len;
len=sizeof(a)/sizeof(a[0])-1;
i=search(a,12,0,len);
printf("%d\n",i);
}