{

std::chrono::steady_clock::time_point begin = std::chrono::steady_clock::now();

//int cnt{0};

std::atomic<unsigned int> cnt{0};

int iterator{1'000'000};

std::mutex lockMutex;

std::future<void> obj1 = std::async(std::launch::async, [&]()

{

//std::lock_guard<std::mutex> guardMutex(lockMutex); //RAII style mechanism

// lockMutex automatically released when guardMutex is out of scope

for(int i{0}; i<iterator; i++)

cnt ++;

});

auto obj2 = std::async(std::launch::async, [&]()

{

//std::lock_guard<std::mutex> guardMutex(lockMutex);

for(int i{0}; i<iterator; i++)

cnt --;

});

obj1.get();

obj2.get();

std::chrono::steady_clock::time_point end = std::chrono::steady_clock::now();

std::cout<<"Time diff "<<std::chrono::duration_cast<std::chrono::microseconds>(end-begin).count()<<"[us]"<<std::endl;

std::cout<<"inc "<<cnt<<std::endl;

}