c++11~c++20 -04-计算一段代码的运行时间

#include    
#include 
#include 
using namespace std;
using namespace chrono;

void CalRunTime() {
	auto t1 = std::chrono::steady_clock::now();
	//run code
	for (int i = 0; i < 10;i++)
	{
		cout << "hello world!n";
		Sleep(10);
	}
	auto t2 = std::chrono::steady_clock::now();

	//秒
	double dr_s = std::chrono::duration(t2 - t1).count();
	cout <<"秒："<< dr_s << endl;
	//毫秒级
	double dr_ms = std::chrono::duration(t2 - t1).count();
	cout << "毫秒：" << dr_ms << endl;
	//微妙级
	double dr_us = std::chrono::duration(t2 - t1).count();
	cout << "微妙：" << dr_us << endl;
	//纳秒级
	double dr_ns = std::chrono::duration(t2 - t1).count();
	cout << "纳秒：" << dr_ns << endl;
}
void main()
{

	CalRunTime();
	
	system("pause");
}

结果：