Object-Oriented Programming Tutorial (live)
Object-Oriented Programming Tutorial (live)¶
# capitalise class names
class Human:
def __init__(self, name):
self.name = name
self.energy = 10
self.friends = []
def __str__(self):
'''
string representation of self
:return: string
'''
s = "Hi, my name is {0}".format(self.name)
return s
def move(self, distance=1):
'''
will reduce energy level eqal to dist travelled
if sufficient energy is available
:return: None
'''
if self.energy < distance:
print("I don't have enough energy to move that far")
else:
self.energy -= distance
def sleep(self):
'''
replenish energy level to 10
:return: None
'''
self.energy = 10
def makefriends(self, friend):
self.friends.append(friend)
friend.friends.append(self)
a = Human('Alice')
b = Human('Bruno')
c = Human('Chantel')
print(a)
Hi, my name is Alice
a.move(3)
print(a.energy)
7
a.sleep()
print(a.energy)
10
a.makefriends(b)
a.makefriends(c)
print("Alice's frinds")
for i in a.friends:
print(i.name)
print("\nBruno's frinds")
for i in b.friends:
print(i.name)
Alice's frinds
Bruno
Chantel
Bruno's frinds
Alice
class Bakery:
def __init__(self, cookies, cost):
self.numcookies = cookies
self.cost = cost
def __str__(self):
s = 'This Bakery has {0} cookies at ${1} each'.format(self.numcookies,
self.cost)
return s
class Baker(Human):
def __init__(self, name):
super().__init__(name)
self.sales = 0
def make_cookies(self, bakery, n_cookies):
bakery.numcookies += n_cookies
def sell_cookies(self, customer, bakery, n_cookies):
if n_cookies > bakery.numcookies:
print("This bakery doesn't have {0} cookies to sell".format(n_cookies))
return
subtotal = n_cookies * bakery.cost
if customer.money < subtotal:
print("The customer can't afford these cookies.")
return
bakery.numcookies -= n_cookies
self.sales += subtotal
customer.money -= subtotal
customer.cookies += n_cookies
class Customer(Human):
def __init__(self, name, money):
super().__init__(name)
self.money = money
self.cookies = 0
def __str__(self):
s = super().__str__() + ' and I have {0} cookies'.format(self.cookies)
return s
romina = Baker('Romina')
print(romina)
Hi, my name is Romina
kelsey = Customer('Kelsey', 10)
print(kelsey)
Hi, my name is Kelsey and I have 0 cookies
my_bakery = Bakery(20, 1.25)
print(my_bakery)
This Bakery has 20 cookies at $1.25 each
romina.sell_cookies(kelsey, my_bakery, 5)
print(kelsey)
print(kelsey.money)
print(my_bakery)
Hi, my name is Kelsey and I have 5 cookies
3.75
This Bakery has 15 cookies at $1.25 each