#include <thread>
#include <fmt/core.h>
#include <chrono>
#include <iostream>
#include <thread>
#include <utility>
#include <iostream>
#include <mutex>

using namespace std::chrono_literals;

std::atomic_int counter = 0;
std::mutex counter_mutex;


void locked_counter() {
  for (int i = 0; i < 5; ++i)
  {
    std::lock_guard<std::mutex> lock(counter_mutex);
    std::this_thread::sleep_for(100ms);
    std::cout << "Thread 1 executing\n";
    ++counter;
  }
}

int main()
{
  std::jthread t2(locked_counter); // pass by value

  for(int i = 0; i < 5; ++i) {
    std::lock_guard<std::mutex> lock(counter_mutex);
    std::cout << "counter is " << counter << std::endl;
  }
}