#include <iostream>
#include <thread>
#include <functional>
 
class MyClass {
public:
  MyClass() {
    std::cout << "construction in: " << std::this_thread::get_id() << std::endl;
  }
 
  MyClass(MyClass const&) {
    std::cout << "copy in: " << std::this_thread::get_id() << std::endl;
  }	
 
  MyClass(MyClass &&) {
    std::cout << "move in: " << std::this_thread::get_id() << std::endl;
  }
};
 
void f(MyClass V) {}
 
int main() {
  {
    MyClass V;
    std::thread t1(f, V);
    t1.join();
  }
  std::cout << "----------\n";
  {
    MyClass V;
    std::thread t2(f, std::ref(V));
    t2.join();
  }
  std::cout << "----------\n";
 
 
  return 0;
}
 

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