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

using namespace std::chrono_literals;

int main()
{
    auto hi = [](char me, int n)
    {
        for (int i = 0; i < n; ++i)
        {
            std::cout << "[thread " << me << "]: hi! " << i << '\n';
            std::this_thread::sleep_for(100ms);
        }
    };

    std::thread t1(hi, '1',         3), 
                t2(hi, '2', 1'000'000);
    t1.detach(); // finaliza al terminar hi
    t2.detach(); // finaliza al terminar el proceso
    std::this_thread::sleep_for(1s);
}