[笔记]c++基础实践《四》chrono库使用

#include <chrono>
#include <thread>
void main(){
  std::this_thread::sleep_for(std::chrono:: milliseconds (1000)); //休眠1000毫秒
}

#include <ctime>
void main(){
  int tick=(int)(std::clock()*1000/ CLOCKS_PER_SEC);

#include <chrono>
#include <thread>
void main(){
    auto start = std::chrono::high_resolution_clock::now();
  std::this_thread::sleep_for(std::chrono:: milliseconds (2000));
  auto end = std::chrono::high_resolution_clock::now();
  uint64_t time  = std::chrono::duration_cast<std::chrono::microseconds>(end - start).count();
    printf("time:%ld\n",time);
}

#include <chrono>
#include <thread>
void main(){
    auto start = std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()).count();
  std::this_thread::sleep_for(std::chrono:: milliseconds (2000));
  uint64_t cur_time = std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()).count();
  uint64_t spend_time  = cur_time - start ;
    printf("time:%ld\n", spend_time);
}