C++Binary search二分法检索的实现算法
C++Binary search二分法检索(折半检索)的实现算法完整源码(定义，实现，main函数测试）
#include <iostream>
/** binary_search function
* \param [in] a array to sort
* \param [in] r right hand limit = \f$n-1\f$
* \param [in] key value to find
* \returns index if T is found
* \return -1 if T is not found
*/
int binary_search(int a[