Pay calculator
Version 2.0

DESIGN


NEW IN THIS VERSION: Data abstraction is enforced by making Time's data private.


  o const float kPayRate = 12;
    

  o int main()

    Runs the calculator.  See program spec for details.

    Collaborator: Time


  o Time
  
    Each Time object represents a time on a 24-hour clock (0:00 to 23:59).
    
    Operations:
    
        void initialize(Time & t)
            Sets t to 99:99.
            
        void read(Time & t, istream & in)
            Reads t from in the format h:mm or hh:mm, where each h and m stands for a single digit.  No error-checking.
            
        void print(const Time & t, ostream & out) 
            Prints t to out in the format described for read.
        
        double difference(const Time & t1, const Time & t2)
            Computes the difference, in hours, between t1 and t2.  The difference is positive if t1 occurs after t2.  In other words, the difference is computed as "t1 - t2".

    Implementation notes: Each time is stored as a pair of integers (hours, minutes) by using a class.  The data is private and the operations are friends of the class.