[C++] quick and dirty object multithread example

/// Honshitsu#9218

#include <vector>
#include <thread>

template <class T>
requires requires (T t){ { t.run() }; }
auto multithread(std::size_t thread_count, T& t)
{
    std::vector<std::jthread> threads;
    threads.reserve(thread_count);
    for (std::size_t i{}; i < thread_count; ++i)
        threads.push_back(std::jthread{ &T::run, &t });
    return threads;
}

#include <iostream>
#include <atomic>
#include <mutex>

struct S
{
    std::mutex mutex;
    unsigned int i{};

    void run()
    {
        std::lock_guard lock{ mutex };
        std::cout << i++ << std::endl;
    }
};

int main()
{
    S s;
    auto threads{ multithread(5, s) };

    for (auto& thread : threads)
        thread.join(); // redundant
}