#include<iostream>
#include<chrono>
#include<thread>
using namespace std;
 
void CheckDuration (std::chrono::duration<int> seconds)
{
  auto start = std::chrono::system_clock::now() + seconds;
  std::this_thread::sleep_for(std::chrono::seconds(1));
  auto stop = std::chrono::system_clock::now();
 
  cout << "Difference = " << std::chrono::duration_cast<std::chrono::seconds>(stop-start).count() << endl;
}
 
int main ()
{
  CheckDuration(std::chrono::duration<int>(0));  // Difference = 1
  CheckDuration(std::chrono::duration<int>(1));  // Difference = 0
  CheckDuration(std::chrono::duration<int>(2));  // Difference = 0
  CheckDuration(std::chrono::duration<int>(3));  // Difference = -1
}

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