Any help would be great,
Your program should, of course, never assign a seat that has already been assigned. When the first class section is full, your program should ask the person if it is acceptable to be placed in the economy section (and vice versa). If yes, then make the appropriate seat assignment. If no, then output the message: Next flight leaves in 3 hours.
Your program should be able to output a list of passengers who have reservations.