stuck with file system ....

i am now doing a Flight Reservation System using classes and file system ...

i know how to store data about passengers info into a file and store flight info into another file.

the problem now is:

Example of flight info:
From: US
To: Aust
Departure: 1200
Arrival: 1800

the flight info is saved in the flight.dat

Example of passenger info:
Name: Amy
Flight: US to Aust

the passenger info is saved in the passenger.dat.

Each flight can takes up to 20 passengers.
how am i suppose to reserved a place for Amy ?

well. in addition to the flight information about departure and arrival, etc., each flight "has a" group of passengers. How you define the group of passengers is up to you. In C++ the group is frequently referred to as a container. Commonly used containers outside of STL include arrays and lists, whereas with STL you also have queues, dequeues, maps, etc. depending on your need. You try to match up the container for the task and your knowledge. In your case declaring an array of passengers of a predetermined size as a data member for each flight seems like a reasonable choice, but you can use whatever you like/feel comfortable with. It would be wise to consider what the default constructor for the passenger class does as that's what will be used to reserve memory for the container you choose.

elad ... i dont get what you mean about declaring array. i dont know anything about STL also. mind showing me some example ?

Code:

struct book
{
   long ID;
   int numAvailable;
};

struct Library
{
  book books[2];
//A Library "has a" group, here an array, of books.  Simplistic use of composition, but illustrates use of a group of user defined class/struct in another class/struct
};

int main()
{
   Library myLibrary; //declare a Library

   //populate the Library
   myLibrary.books[0].ID = 4365;
   myLibrary.books[0].numAvailable = 1;
   myLibrary.books[1].ID = 1111;
  myLibrary.books[1].numAvailable = 2;
  
  //have user request a book
  cout << "which book number do you want?" << endl;
  long inputID;
  cin >> inputID;
  
  int i;
  bool found = false;

  //check the Library to see if the book is there
  for(i = 0; i < 2; ++i)
  {
     if(inputID == myLibrary.books[i].ID)
     { 
        //the book is in the Library
        found = true;

        //tell how many copies are available
        cout << "there are " << myLibrary.books[i].numAvailable << " copies of book # " << myLibrary.books[i].ID << " available." << endl;

        //stop search
        i = 3;
      }
   }
    //if book not found in Library let user know
    if(!found)
      cout << "sorry, we don't have a book with ID number " << inputID << " available.  Please check with your local university book store." << endl;
}