C/C++中的算法速度测试仪

我必须以毫秒为单位计算算法的速度.在C/C++中,我该怎么做？我需要在输入之前和输出之后写smth但是究竟是什么？

解决方法

您可以使用< time.h>中的clock()函数.
clock()显示自程序启动以来已经过了多少个刻度.宏CLOCKS_PER_SEC包含每秒的滴答数,因此您实际上可以获得时间.

//We start measuring here. Remember what was the amount of ticks in the 
//beginning of the part of code you want to test:
int start = clock();
//<...>
//Do your stuff here
//<...>
int end = clock();//Now check what amount of ticks we have Now. 
//To get the time,just subtract start from end,and divide by CLOCKS_PER_SEC.
std::cout << "it took " << end - start << "ticks,or " << ((float)end - start)/CLOCKS_PER_SEC << "seconds." << std::endl;