第七章 用户输入和while循环
动手试一试代码实现
（1）习题内容
7-1 汽车租赁：编写一个程序，询问用户要租赁什么样的汽车，并打印一条消息，如“Let me see if I can find you a Subaru”。
7-2 餐馆订位：编写一个程序，询问用户有多少人用餐。如果超过8人，就打印一条消息，指出没有空桌；否则指出有空桌。
7-3 10的整数倍：让用户输入一个数字，并指出这个数字是否是10的整数倍。
7-4 比萨配料：编写一个循环，提示用户输入一系列的比萨配料，并在用户输入‘quit’时结束循环。每当用户输入一种配料后，都打印一条消息，说我们会在比萨中添加这种配料。
7-5 电影票：有家电影院根据观众的年龄收取不同的票价：不到3岁的观众免费；3~12岁的观众为10美元；超过12岁的观众为15美元。请编写一个循环，在其中询问用户的年龄，并指出其票价。
备注：7-5练习题的代码实现在7-6练习题中。
7-6 三个出口：以另一种方式完成练习7-4或练习7-5，在程序中采取如下所有做法。
①在while循环中使用条件测试来结束循环。（备注：不单独编写）
②使用变量active来控制循环结束的时机。
③使用break语句在用户输入‘quit’时退出循环。
7-8 熟食店：创建一个名为 sandwich_orders 的列表，在其中包含各种三明治的名字；再创建一个名为finished_sandwiches的空列表。遍历列表sandwich_orders，对于其中的每种三明治，都打印一条消息，如 I made your tuna sandwich，并将其移到列表finish_sandwiches。所有三明治都制作好后，打印一条消息，将这些三明治列出来。
7-9 五香烟熏牛肉（pastrami）卖完了：使用为完成练习 7-8 而创建的列表sandwich_orders，并确保‘pastrami’在其中至少出现了三次。在程序开头附近添加这样的代码：打印一条消息，指出熟食店的五香烟熏牛肉卖完了；再使用一个while循环将列表sandwich_orders中的‘pastrami’都删除。确认最终的列表finish_sandwiches中不包含‘pastrami’。
7-10 梦想的度假胜地：编写一个程序，调查用户梦想的度假胜地。使用类似于“If you could visit one place in the world,where would you go?”的提示，并编写一个打印调查结果的代码块。
# 7-1
car=input("Please tell me what's car you want: \n")
print("Let me see if I can find you a "+car+".")
# 7-2
meal_number=input("\nExcuse me,please tell me how many people have meal:")
meal_number=int(meal_number)
if meal_number>8:
print("Excuse me,there is not empty table.")
else:
print("There is empty table.")
# 7-3
number=input("\nPlease input a number,I will tell you if it can be divisible by 10:")
number=int(number)
if number % 10 == 0:
print("it can be divisible by 10.")
else:
print("it can't be divisible by 10.")
# 7-4
pizza_ingredient="\nPlease input a ingredient of pizza:"
pizza_ingredient+="\nEnter 'quit' when you are finished."
ingredients=""
while ingredients != 'quit':
ingredients=input(pizza_ingredient)
if ingredients != 'quit':
print("We will add "+ingredients+" in pizza.")
# 7-6_2
user_age2="\nPlease tell me your age:"
user_age2+="\nEnter 'quit' end the program."
active=True
while active:
age=input(user_age2)
if age == 'quit':
active=False
elif int(age) < 3:
print("The ticket price is free.")
elif int(age) <= 12:
print("The ticket price is 10.")
elif int(age) > 12:
print("The ticket price is 15.")
# 7-6_3
user_age3="\nPlease tell me your age:"
user_age3+="\nEnter 'quit' end the program."
while True:
age=input(user_age3)
if age == 'quit':
break
elif int(age) < 3:
print("The ticket price is free.")
elif int(age) <= 12:
print("The ticket price is 10.")
elif int(age) > 12:
print("The ticket price is 15.")
print("\n")
# 7-8
sandwich_orders=['egg','beef','tuna']
finished_sandwiches=[]
while sandwich_orders:
current_sandwich=sandwich_orders.pop()
print("I made your "+current_sandwich+" sandwich.")
finished_sandwiches.append(current_sandwich)
print("\nThe following sandwiches have been made:")
for finished_sandwich in finished_sandwiches:
print(finished_sandwich.title()+" sandwich")
# 7-9
sandwich_orders=['egg','pastrami','beef','pastrami','tuna','pastrami']
print("\nThe deli's pastrami is sold out.")
while 'pastrami' in sandwich_orders:
sandwich_orders.remove('pastrami')
finished_sandwiches=sandwich_orders
print("The sandwich orders:")
print(finished_sandwiches)
# 7-10
survey={}
survey_actice=True
while survey_actice:
respondent=input("\nWhat is your name?")
reply=input("Hello,"+respondent.title()+",if you could visit one place in the world,where would you go?")
survey[respondent]=reply
go_on=input("Is there anyone else who wants to participate in the investigation?(yes/no)")
if go_on == 'no':
survey_actice=False
print("\n--- survey results ---")
for respondent,reply in survey.items():
print(respondent.title()+" would like to visit "+reply.title()+".")
