C++获取程序运行时间

#include <iostream>

#include <time.h>

#include <windows.h>

#include<chrono>

using namespace std;

using namespace std::chrono;

int main()

{

	struct timeval time1;

	/*cout << "秒:" << duration_cast<seconds>(system_clock::now ().time_since_epoch ()).count () << endl;

	cout << "毫秒:" << duration_cast<milliseconds>(system_clock::now ().time_since_epoch ()).count () << endl;

	cout << "微秒:" << duration_cast<microseconds>(system_clock::now ().time_since_epoch ()).count () << endl;

	cout << "纳秒:" << duration_cast<nanoseconds>(system_clock::now ().time_since_epoch ()).count () << endl;*/

	for (int i = 0; i < 100; i++)

	{

		int count = 0;

		int t1 = duration_cast<microseconds>(system_clock::now().time_since_epoch()).count();

		//cout << "微秒:" << duration_cast<microseconds>(system_clock::now ().time_since_epoch ()).count () << endl;

		for (int j = 0; j < 120000; j++)

		{

			if (j % 3 == 0)

				if(j % 9 == 0)

					count += 1;

				else

					count += 2;

		}

		int t2 = duration_cast<microseconds>(system_clock::now().time_since_epoch()).count();

		cout << t2 - t1 << endl;

		//cout << "微秒:" << duration_cast<microseconds>(system_clock::now ().time_since_epoch ()).count () << endl;

	}

	return 0;

}