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

void func()
{
   for (int i = 0; i < 100; ++i)
   {
      std::cout << i << "\n";
      std::this_thread::sleep_for(std::chrono::milliseconds(2));
   }
}

int main()
{
   std::thread t1(func);
   std::thread t2(func);
   t1.join();
   t2.join();
   return 0;
}