[...]

int getRandomTime(int start, int end){

random_device seed;
mt19937 engine(seed());
uniform_int_distribution<int> dist(start,end);

return dist(engine);
};

class Worker{
public:
Worker(string n):name(n){};

void operator() (promise<void>&& preparedWork, shared_future<void> boss2WorkerStartWork,
promise<void>&& doneWork, shared_future<void>boss2WorkerGoHome ){

// prepare the work and notfiy the boss
int prepareTime= getRandomTime(500,2000);
sleep_for(milliseconds(prepareTime));
preparedWork.set_value();
cout << name << ": " << "Work prepared after " << prepareTime << " milliseconds." << endl;

// still waiting for the permission to start working
boss2WorkerStartWork.wait();

// do the work and notify the boss
int workTime= getRandomTime(200,400);
sleep_for(milliseconds(workTime));
doneWork.set_value();
cout << name << ": " << "Work done after " << workTime << " milliseconds." << endl;

// still waiting for the permission to go home
boss2WorkerGoHome.wait();

}
private:
string name;
};

int main(){

cout << endl;

// define the promise => Instruction from the boss
promise<void> startWorkPromise;
promise<void> goHomePromise;

// get the shared futures from the promise
shared_future<void> startWorkFuture= startWorkPromise.get_future();
shared_future<void> goHomeFuture= goHomePromise.get_future();

promise<void> herbPrepared;
future<void> waitForHerbPrepared= herbPrepared.get_future();
promise<void> herbDone;
future<void> waitForHerbDone= herbDone.get_future();
Worker herb(" Herb");
thread herbWork(herb,move(herbPrepared),startWorkFuture,move(herbDone),goHomeFuture);

// start thread scott, bjarne, andrei, andrew and david
[...]

cout << "BOSS: PREPARE YOUR WORK.\n " << endl;

// waiting for the worker
waitForHerbPrepared.wait(), waitForScottPrepared.wait(), waitForBjarnePrepared.wait(), waitForAndreiPrepared.wait(), waitForAndrewPrepared.wait(), waitForDavidPrepared.wait();

// notify the worker about the begin of the work
cout << "\nBOSS: START YOUR WORK. \n" << endl;
startWorkPromise.set_value();

// waiting for the worker
waitForHerbDone.wait(), waitForScottDone.wait(), waitForBjarneDone.wait(), waitForAndreiDone.wait(), waitForAndrewDone.wait(), waitForDavidDone.wait();

// notify the worker about the end of the work
cout << "\nBOSS: GO HOME. \n" << endl;
goHomePromise.set_value();

herbWork.join();
scottWork.join();
bjarneWork.join();
andreiWork.join();
andrewWork.join();
davidWork.join();

}