задача к курсовой (Багаж пассажира)

#include <ctime>
#include <cstdlib>
#include <cmath>
#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <iomanip>
#include <vector>
#include <iterator>
 
class Luggage {
 public:
  Luggage() : weight(0), numberOfItems(0) {}
  Luggage(double weight, int numberOfItems) : weight(weight),
    numberOfItems(numberOfItems) {}
  double getWeight() const { return weight; }
  int getNumberOfItems() const { return numberOfItems; }
  double getAverageWeight() const {
    return getWeight() / getNumberOfItems();
  }
 private:
  double weight;
  int numberOfItems;
};
 
std::istream &operator>>(std::istream &stream, Luggage &luggage) {
  std::string line;
  std::getline(stream, line);
  std::stringstream stringStream(line);
  double weight, numberOfItems;
  stringStream >> weight >> numberOfItems;
  luggage = Luggage(weight, numberOfItems);
  return stream;
};
 
std::ofstream &operator<<(std::ofstream &stream, const Luggage &luggage) {
  stream << luggage.getWeight() << " " << luggage.getNumberOfItems() <<
    std::endl;
  return stream;
}
 
std::ostream &operator<<(std::ostream &stream, const Luggage &luggage) {
  return stream << "Luggage{" <<
    std::fixed << std::setprecision(3) <<
    "weight=" << luggage.getWeight() << "," <<
    "numberOfItems=" << luggage.getNumberOfItems() << "," <<
    "averageWeight=" << luggage.getAverageWeight() << "}";
}
 
class LuggageStorage {
 public:
  typedef std::vector<Luggage>::iterator Iterator;
  typedef std::vector<Luggage>::const_iterator ConstIterator;
  LuggageStorage(const std::string &fileName) : fileName(fileName),
    storage() {
    loadFromFile();
  }
  virtual ~LuggageStorage() {
    saveToFile();
  }
  Iterator begin() { return storage.begin(); }
  ConstIterator begin() const { return storage.begin(); }
  Iterator end() { return storage.end(); }
  ConstIterator end() const { return storage.end(); }
  
  Iterator insert(Iterator position, const Luggage &luggage) {
    return storage.insert(position, luggage);
  }
  
  void clear() {
    storage.clear();
  }
 
  size_t getSize() const {
    return storage.size();
  }
 
  void saveToFile() {
    std::ofstream stream(fileName.c_str());
    for (ConstIterator i = storage.begin(); i != storage.end(); ++i) {
      stream << *i;
    }
  }
  void loadFromFile() {
    storage.clear();
    std::ifstream stream(fileName.c_str());
    while (!stream.eof()) {
      Luggage luggage;
      stream >> luggage;
      if (!stream.eof()) {
        storage.push_back(luggage);
      }
    }
  }
 private:
  std::string fileName;
  std::vector<Luggage> storage;
};
 
int main(int argc, char *argv[]) {
  srand(time(0));
  // загружается и сохраняется в файл автоматически
  LuggageStorage s("tutor5032.txt");
 
  /*
  // вот так можно генерировать случайный багаж для файла 
  s.clear();
  for (int i = 0; i < 22; ++i) {
    s.insert(s.end(), Luggage((rand() % 10000) / 100., 1 + rand() % 10));
  }
  */
 
  // вывод на экран
  std::copy(s.begin(), s.end(), std::ostream_iterator<Luggage>(std::cout, "\n"));
 
  /*
   * а) Найти багаж, средний вес одной вещи в котором отличается не
   * более чем на 0,3 кг от общего среднего веса вещи.
   */
  
  double totalWeight = 0, totalNumberOfItems = 0;
  for (LuggageStorage::ConstIterator i = s.begin(); i != s.end(); ++i) {
    totalWeight += i->getWeight();
    totalNumberOfItems += i->getNumberOfItems();
  }
  double averageWeight = totalWeight / totalNumberOfItems;
  std::cout << "Average weight of all luggage is " << averageWeight <<
    "." << std::endl;
  for (LuggageStorage::ConstIterator i = s.begin(); i != s.end(); ++i) {
    if (fabs(i->getAverageWeight() - averageWeight) <= 0.3) {
      std::cout << "Luggage average weight is near average: " << *i <<
        std::endl;
    }
  }
  
 
  /*
   * Ну и так далее...
   */
  
  return 0;
}