시간 측정을 위해 chrono 사용법 정리

* 상세 내용 아래 참조
출처1: https://fias.uni-frankfurt.de/pm/issues/566
         첨부 PDF 참조
         https://fias.uni-frankfurt.de/pm/attachments/download/1496/chrono.pdf

출처2: http://www.cplusplus.com/reference/chrono/

시간 측정을 위해 chrono 사용법 간단 정리

1:  #include <iostream>  
2:  #include <chrono>  
3:  using namespace std;  
4:  using namespace chrono; // std 내에 chrono 가 존재  
5:  int main(void) {  
6:      system_clock::time_point start = system_clock::now();  
7:      int a = 0;  
8:      for (int i = 0; i < 10000000; i++) {  
9:          a++;  
10:      }  
11:      system_clock::time_point end = system_clock::now();  
12:      microseconds microSec = duration_cast<microseconds>(end - start);  
13:      cout << microSec.count() << " us\n";  
14:      return 0;  
15:  }  

시작
system_clock::time_point start = system_clock::now();

끝
system_clock::time_point end = system_clock::now();

시간 계산
microseconds microSec = duration_cast<microseconds>(end - start);

출력
cout << microSec.count() << " us\n";

us (micro seconds) : 1 / 1000000 sec
ms (milli seconds) : 1 / 1000 sec