python 学习笔记之（四）while循环处理列表和字典

1.在列表之间移动元素
一个网站有三个未确认的用户需要登录，将其存放在一个列表内。通过while判断该列表非空，在while循环内部做确认处理，将列表底部的元素弹出存放在新的列表内，即可确认用户已经登陆。

示例1.

unconfirmed_users = ['张三' , '李四', '王二']confirmed_users = []while unconfirmed_users:    current_user = unconfirmed_users.pop()    print("Verifying user:" + current_user.title())    confirmed_users.append(current_user)print("The following users have been confired:")for confirmed_user in confirmed_users:    print(confirmed_user)----------Result：    Verifying user:王二    Verifying user:李四    Verifying user:张三    The following users have been confired:    王二    李四    张三

2.删除包含特定值的所有列表元素
在前面的章节使用函数remove()，来删除列表中的特定值，只能删除一个列表中的元素。假如列表中有许多相同的元素则可用“while”对此元素做判断，进行逐个删除，直至列表中不再包含指定元素。
示例2.

pets = ['dog', 'cat', 'pig', 'cat']while 'cat' in pets:    pets.remove('cat')print(pets)----------Result：    ['dog', 'pig']

3.使用用户输入来填充字典、
创建一个字典来循环存入，被访用户的姓名和回答。
示例3.

responses = {}active = Truewhile active:    name = input("\nWhat is your name? ")    response = input("\n Which sport do you like? ")    responses[name] = response    repeat  = input("Do you want anthre person respond? (yes/no)")    if repeat == 'no':        active = Falsefor name, response in responses.items():    print(name + " would like to play " + response + '.')----------Result：    What is your name? 张三    Which sport do you like? 吃鸡    Do you want anthre person respond? (yes/no)no    张三 would like to play 吃鸡.    Process finished with exit code 0