const secureBooking = function () {
  let passengerCount = 0;
  return function () {
    passengerCount++;
    console.log(`${passengerCount} passengers`);
  };
};

const booker = secureBooking();
booker();
booker();
booker();

// console.dir(secureBooking);

const boardPassengers = function (n, wait) {
  const perGroup = n / 3;

  setTimeout(function () {
    console.log(`We are now boarding all ${n}`);
    console.log(`There are 3 groups, each with ${perGroup}`);
  }, wait * 1000);
  console.log(`Will start boarding in ${wait} seconds`);
};

const perGroup = 1000;
boardPassengers(180, 3);