二分查找法C++代码实现

int binary_search(int array[],int n,int value)  //array 为有序数组，n数组大小，value为要查找的值
{
    int begin = 0;
    int end = n-1;
    int mid ;
    while(begin<=end)
    {
        mid = begin +(end - begin)/2;//防止加法溢出
        if(array[mid]==value)
         {   
             return mid;
         }
         else if(value<array[mid])
         {
             end = mid - 1;
         }
         else
         {
             begin = mid + 1;
         }
    }
    return -1;      
}