用户输入和 while 循环
input() 函数的工作原理
input() 函数让程序暂停运行，等待用户输入一些文本。获取文本输入后，python 将其赋予一个变量，以便使用
message = input("Tell me something, and I will repeat it back to you: ")
print(message)
Tell me something, and I will repeat it back to you: Hello Hello
while 循环简介
for 循环针对集合中的每个元素执行一个代码块，而 while 循环则不断地运行，直到指定的条件不再满足为止
使用 while 循环
current_number = 1
while current_number <= 5:
print(current_number)
current_number += 1
输出 1 2 3 4 5
让用户何时退出
message = ''
while message != 'quit':
message = input("Tell me something, and I will repeat it back to you: ")
print(message)
使用标志
active = True
message = ''
while active:
message = input("Tell me something, and I will repeat it back to you: ")
if message == 'quit':
active = False
else:
print(message)
使用 break
message = ''
while True:
message = input("Tell me something, and I will repeat it back to you: ")
if message == 'quit':
break
else:
print(message)
在循环中使用 continue
current_number = 0
while current_number < 10:
current_number += 1
if current_number % 2 == 0:
continue
print(current_number)
输出 1 3 5 7 9
使用 while 循环处理列表和字典
unconfirmed_users = ['alice', 'brian', 'candace']
confirmed_uses = []
while unconfirmed_users:
current_user = unconfirmed_users.pop()
print(f"Verifying user: {current_user.title()}")
confirmed_uses.append(current_user)
print(confirmed_uses)
输出 [‘alice’, ‘brian’, ‘candace’]