Methods of Threads in Practice

// threadMethods.cpp
#include <iostream>
#include <thread>
using namespace std;
int main(){
  cout << boolalpha << endl;
  cout << "hardware_concurrency()= "<< thread::hardware_concurrency() << endl;
  thread t1([]{cout << "t1 with id= " << this_thread::get_id() << endl;});
  thread t2([]{cout << "t2 with id= " << this_thread::get_id() << endl;});
  cout << endl;
  cout << "FROM MAIN: id of t1 " << t1.get_id() << endl;
  cout << "FROM MAIN: id of t2 " << t2.get_id() << endl;
  cout << endl;
  swap(t1,t2);
  cout << "FROM MAIN: id of t1 " << t1.get_id() << endl;
  cout << "FROM MAIN: id of t2 " << t2.get_id() << endl;
  cout << endl;
  cout << "FROM MAIN: id of main= " << this_thread::get_id() << endl;
  
  cout << endl;
  
  cout << "t1.joinable(): " << t1.joinable() << endl;
  
  cout << endl;
  t1.join();
  t2.join();
  
  cout << endl;
  
  cout << "t1.joinable(): " << t1.joinable() << endl;
  cout << endl;
}