c++二分查找

#include<iostream> 
using namespace std;
int search(int a[],int key,int low,int high)
{
int mid;
while(low<high)
{
mid=(low+high)/2;
if(key<a[mid]){high=mid-1;continue;}
if(key>a[mid]){low=mid+1;continue;}

if(key==a[mid])return mid;break;
}
if(low>high)cout<<"对不起，没有这个数！"<<endl;
}
void main()
{
int a[9]={12,23,45,51,56,62,67,68,72},i,b;

   for(i=0;i<9;i++)
  { 
     cout<<a[i]<<" ";
  }
cout<<"请输入您要查找的数字：";
cin>>b;

cout<<"您要查找的数为数组a["<<search(a,b,0,8)<<"]"<<endl;