CLOCKS

CLOCKS_PER_SEC不匹配std :: clock（）的结果(CLOCKS_PER_SEC Not Matching Results From std::clock())

我正在使用以下短程序来测试std::clock() ：

#include <ctime> #include <iostream> int main() { std::clock_t Begin = std::clock(); int Dummy; std::cin >> Dummy; std::clock_t End = std::clock(); std::cout << "CLOCKS_PER_SEC: " << CLOCKS_PER_SEC << "\n"; std::cout << "Begin: " << Begin << "\n"; std::cout << "End: " << End << "\n"; std::cout << "Difference: " << (End - Begin) << std::endl; }

但是，在等待几秒钟输入“虚拟”值后，我得到以下输出：

CLOCKS_PER_SEC: 1000000 Begin: 13504 End: 13604 Difference: 100

这显然没有多大意义。 无论等待多久，差异总是在100左右。

我错过了什么？ 是否有一些我忘记包含的标题？

我使用Xcode和GCC 4.2。

I'm using the following short program to test std::clock():

#include <ctime> #include <iostream> int main() { std::clock_t Begin = std::clock(); int Dummy; std::cin >> Dummy; std::clock_t End = std::clock(); std::cout << "CLOCKS_PER_SEC: " << CLOCKS_PER_SEC << "\n"; std::cout << "Begin: " << Begin << "\n"; std::cout << "End: " << End << "\n"; std::cout << "Difference: " << (End - Begin) << std::endl; }

However, after waiting several seconds to input the "dummy" value, I get the following output:

CLOCKS_PER_SEC: 1000000 Begin: 13504 End: 13604 Difference: 100

This obviously doesn't make much sense. No matter how long I wait, the difference is always somewhere around 100.

What am I missing? Is there some header I forgot to include?

I'm using Xcode with GCC 4.2.

最满意答案

clock()计算CPU时间，因此如果它坐在等待输入的位置，它不会增加任何时间。

clock() counts CPU time, so it's not adding any time if it's sitting around waiting for input.