#include <thread>
#include <string>
#include <iostream>
#include <chrono>

/*
 * Compile with 'g++ -pthread a.cpp'
 *
 * The order of printing is not well-defined
 */

using namespace std;

void f1() {
	cout << "Hello " << endl;
	this_thread::sleep_for(std::chrono::seconds(2));
	cout << "World" << endl;
}

void f2() {
	this_thread::sleep_for(std::chrono::seconds(1));
	cout << "Parallel" << endl;
}

int main() {
	thread t1(f1);
	thread t2(f2);

	t1.join();
	t2.join();

	return 0;
}