Section 1.3 • Programming Style 3
1.3 PROGRAMMING STYLE
Exercises 1.3
E1. What classeswouldyoudefineinimplementing the following projects? Whatmethodswould your classes
possess?
(a) A program to store telephone numbers.
Answer
The program could use classes called Phone_book and Person. The methods for a Phone_book
object would include look_up_name, add_person, remove_person. The methods for a Person
object would include Look_up_number. Additional methods to initialize and print objects of
both classes would also be useful.
(b)
A program to play Monopoly.
Answer
The program could use classes called Game_board, Property, Bank, Player, and Dice. In addition
toinitializationand printing methods forall classes, the following methods would beuseful. The
class
Game_boardneeds methods next_card and operate_jail. The class Property needs methods
change_owner, look_up_owner, rent, build, mortgage, and unmortgage. The class Bank needs
methods
payandcollect. The class Playerneeds methods roll_dice, move_location, buy_property
and pay_rent. The class Dice needs a method roll.
(c)
A program to play tic-tac-toe.
Answer
The program could use classes called Game_board and Square. The classes need initializa-
tion and printing methods. The class
Game_board would also need methods make_move and
is_game_over. The class Square would need methods is_occupied, occupied_by, and occupy.
(d)
A program to model the build up of queues of cars waiting at a busy intersection with a traffic light.
Answer
TheprogramcoulduseclassesCar, Traffic_light,andQueue. Theclasseswouldallneedinitializa-
tionand printingmethods. The class
Traffic_lightwould needadditionalmethods change_status
and status. The class Queue would need additional methods add_car and remove_car.
E2.
Rewrite the following class definition, which is supposed to model a deck of playing cards, so that it
conforms to our principles of style.
class a { // a deck of cards
int X; thing Y1[52]; /
*
X is the location of the top card in the deck. Y1 lists the cards.
*
/ pub-
lic:
a();
void
Shuffle(); // Shuffle randomly arranges the cards.
thing d()
; // deals the top card off the deck
}
;
Answer
class Card_deck {
Card deck[52];
int
top_card;
public:
Card_deck();
void
Shuffle();
Card deal();
};
