#include <thread>
#include <atomic>
#include <vector>
#include <unistd.h>
using namespace std;

int main() {
  vector<thread> threads;
  atomic<bool> done { false };
  for (int i = 0; i < 20; i++) {
    threads.emplace_back([&]() {
      while (!done) { usleep(10000); }
    });
    threads.back().detach();
  }
  done = true;
  sleep(1);
  return 0;
}