7-6 三个出口

1. 项目

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。

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。
 在 while 循环中使用条件测试来结束循环。
 使用变量 active 来控制循环结束的时机。
 使用 break 语句在用户输入'quit'时退出循环。

 

2. 代码

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

age = "" prompt = "Hello, How old are you?" #在 while 循环中使用条件测试来结束循环 while age != 'quit':     age = input(prompt)     if age != 'quit':         age = int(age)         if age <= 3:             ticket_fee = 0             print("You are free for watch movie...\n")         elif age > 3 and age <= 12:             ticket_fee = 10             print("You should pay " + str(ticket_fee) + "$ to watch movie.\n")         elif age > 12:             ticket_fee = 15             print("You should pay " + str(ticket_fee) + "$ to watch movie.\n")

　　

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

age = "" # 使用变量 active 来控制循环结束的时机 active = True prompt = "Hello, How old are you?"   while active:     age = input(prompt)     if age == 'quit':         active = False     else:         age = int(age)         if age <= 3:             ticket_fee = 0             print("You are free for watch movie...\n")         elif age > 3 and age <= 12:             ticket_fee = 10             print("You should pay " + str(ticket_fee) + "$ to watch movie.\n")         elif age > 12:             ticket_fee = 15             print("You should pay " + str(ticket_fee) + "$ to watch movie.\n")

　　

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

age = "" prompt = "Hello, How old are you?" while True:     age = input(prompt)     if age == 'quit':         # 使用 break 语句在用户输入'quit'时退出循环         break     else:         age = int(age)         if age <= 3:             ticket_fee = 0             print("You are free for watch movie...\n")         elif age > 3 and age <= 12:             ticket_fee = 10             print("You should pay " + str(ticket_fee) + "$ to watch movie.\n")         elif age > 12:             ticket_fee = 15             print("You should pay " + str(ticket_fee) + "$ to watch movie.\n")

 

3. 执行结果

?

1 2 3 4 5 6 7 8 9 10 11

D:\python编程：从入门到实践\venv\Scripts\python.exe "D:/python编程：从入门到实践/第7章 用户输入和while循环/parrot.py" _______________________________3rd_________________________________ Hello, How old are you?1 You are free for watch movie...   Hello, How old are you?33 You should pay 15$ to watch movie.   Hello, How old are you?quit   Process finished with exit code 0