adding the date class files

lectures/03_classes_I/date.h

@@ -0,0 +1,36 @@
+// File:     date.h
+// Purpose:  Header file with declaration of the Date class, including
+//   member functions and private member variables.
+
+class Date {
+public:
+  Date();
+  Date(int aMonth, int aDay, int aYear);
+
+  // ACCESSORS
+  int getDay() const;
+  int getMonth() const;
+  int getYear() const;
+
+  // MODIFIERS
+  void setDay(int aDay);
+  void setMonth(int aMonth);
+  void setYear(int aYear);
+  void increment();
+
+  // other member functions that operate on date objects
+  bool isEqual(const Date& date2) const;  // same day, month, & year?
+  bool isLeapYear() const;     
+  int lastDayInMonth() const;
+  bool isLastDayInMonth() const;
+  void print() const;                     // output as month/day/year
+
+private:  // REPRESENTATION (member variables)
+  int day;
+  int month;
+  int year;
+};
+
+// prototypes for other functions that operate on class objects are often
+// included in the header file, but outside of the class declaration
+bool sameDay(const Date &date1, const Date &date2); // same day & month?