//------------------------------------------------------------------------
// fraction.h -- interface for a Fraction class
//
//  A Fraction represents a rational number, which is not a built-in type
//  in C++.  As we learned in gradeschool, a fraction consists of a 
//  numerator and a denominator.  We will describe fractions as [num/den].
//
//------------------------------------------------------------------------

class Fraction
{
 public:
   // SetValue -- set the fraction, given the numerator and denominator
   // PRE: denominator != 0
   // POST: this fraction = [numberator/denominator]
   void SetValue (int numerator, int denominator);

   // GetValue -- get the value as a floating-point number
   //             (may lose precision)
   // PRE: SetValue() has been called
   // FCTVAL: closest double representation of this fraction
   double GetValue ();

   // Add -- add two fractions.  Returns a third, new fraction
   // PRE: SetValue() has been called on this instance and on rhs
   // FCTVAL: a fraction representing this instance plus rhs
   // INVAR: neither this instance nor rhs is changed
   Fraction Add (Fraction rhs);


 private:
   int num;               // the numerator
   int den;               // the denominator
};