The program of Figs. 10.6–10.8 demonstrates a
Date class, which uses overloaded prefix and postfix increment operators to add 1 to the day in a
Date object, while causing appropriate increments to the month and year if necessary. The
Date header (Fig. 10.6) specifies that
public interface includes an overloaded stream insertion operator (line 11), a default constructor (line 13), a
setDate function (line 14), an overloaded prefix increment operator (line 15), an overloaded postfix increment operator (line 16), an overloaded
+= addition assignment operator (line 17), a function to test for leap years (line 18) and a function to determine whether a day is the last day of the month (line 19).