2.22

prompt = "
Please tell me your age."
prompt += "
Enter 'quit' to end."
message = ''
switch = True
while switch:

    message = input(prompt)
    if message == 'quit':
        switch = False
    else:
        message = int(message)
        if message < 3:
            price = 0
        if message >= 3 and message <= 12:
            price = 10
        if message > 12:
            price = 15
        print("Your ticket cost is $" + str(price) + ".")


unconfiemed_users = ['aa','bb','cc']
confiemrd_users = []
while unconfiemed_users:
    current_user = unconfiemed_users.pop()

    print("Verifying user:" + current_user.title())
    confiemrd_users.append(current_user)

print("
The following users have been confirmed:")
for confirmed_user in confiemrd_users:
    print(confirmed_user.title())

pets = ['dog', 'cat', 'dog', 'goldfish', 'cat', 'rabbit', 'cat']
print(pets)
while 'cat' in pets:
    pets.remove('cat')
    print(pets)
"""
responses = {} # 设置一个标志，指出调查是否继续 经典

polling_active = True
while polling_active: # 提示输入被调查者的名字和回答

    name = input("
What is your name? ")
    response = input("Which mountain would you like to climb someday? ")

    responses[name] = response # 将答卷存储在字典中

    repeat = input("Would you like to let another person respond? (yes/ no) ")# 看看是否还有人要参与调查
    if repeat == 'no':
        polling_active = False

print("
--- Poll Results ---")# 调查结束，显示结果
for name, response in responses.items():
    print(name + " would like to climb " + response + ".")
"""



# 练习7-8

sandwich_orders = ['aa', 'bb', 'cc']
finished_sandwiches = []
while sandwich_orders:
    making_sandwich = sandwich_orders.pop()
    print("
I made your " + making_sandwich + " sandwiches.")
    # finished_sandwiches.append(finished_sandwiches) #  >>>[[...], [...], [...]]问题
    finished_sandwiches.append(making_sandwich)
print(finished_sandwiches)

sandwich_orders = ['aa', 'bb', 'cc', 'pastrami','pastrami','pastrami']
print()
while 'pastrami' in sandwich_orders:
    sandwich_orders.remove('pastrami')
    print(sandwich_orders)
    if 'pastrami' not in sandwich_orders:
        print('Pastrami was sold out.')

# 定义为形，调用为实。
# 练习8-1
def display_message(learn):
    """What did I learned?"""
    print("I learned " + learn + " in this.")


display_message("kannsu")


def favorite_book(title):
    """print my favorite book"""
    print("One of my favorite books is " + title + ".")

favorite_book("Building.Machine.Learning.Systems.with.Python")