作业：编写登录接口

    1. 让用户输入用户名密码
    2. 认证成功后显示欢迎信息
    3. 输错三次后退出程序
升级要求：
    1. 可以支持多个用户登录（提示，通过列表存多个账户信息）
    2. 用户三次认证失败后，退出程序，再次启动程序尝试登录时，还是锁定状态（提示：需把用户锁定的状态存到文件里）

'''
基础要求：
    1. 让用户输入用户名密码
    2. 认证成功后显示欢迎信息
    3. 输错三次后退出程序
升级要求：
    1. 可以支持多个用户登录（提示，通过列表存多个账户信息）
    2. 用户三次认证失败后，退出程序，再次启动程序尝试登录时，还是锁定状态（提示：需把用户锁定的状态存到文件里）
'''
version 1.0
# 1.0版本存在一些小漏洞。
user_info = {
    'Catalog_Spri' : {'user_pwd' : 'C.Spridsb', 'times' : 0},
    'Egon' : {'user_pwd' : 'egondsb', 'times' : 0},
    'Alex' : {'user_pwd' : 'alexdsb', 'times' : 0},
}

count = 1
while count <= 3:
    name = input('Please input your account>>:')
    pwd = input('Please input your password>>:')
    f = open('lock.txt', mode='r+', encoding='UTF-8')
    is_lock = f.readlines()
    if name in is_lock:
        print('Your account has been locked, please try again later.')
        break
    if name in user_info and pwd == user_info[name]['user_pwd']:
        print('Welcome to the new world.')
        user_info[name]['times'] = 0
        break
    if (name not in user_info) or pwd != user_info[name]['user_pwd']:
        print('Your account or password was wrong.')
        if name in user_info:
            user_info[name]['times'] += 1
            if user_info[name]['times'] == 3:
                f.write(name)
    f.close()
    count += 1

version 2.0
# 相对1.0版本，2.0版本改进了一些机制。
while True:
    name = input('Please input your account>>:')
    pwd = input('Please input your password>>:')
    f = open('lock.txt', mode='r+', encoding='UTF-8')
    is_lock = f.readlines()
    if name in is_lock:
        print('Your account has been locked, please try again later.')
        break
    if name not in user_info:
        print("Your account can't be found, please try again.")
        continue
    if pwd == user_info[name]['user_pwd']:
        print('Welcome to the new world.')
        user_info[name]['times'] = 0
        break
    if pwd != user_info[name]['user_pwd']:
        print('Your account or password was wrong, please try again.')
        if name in user_info:
            user_info[name]['times'] += 1
            if user_info[name]['times'] == 3:
                f.write(name)
                break
    f.close()

version 2.1
# 2.1版本做了一些优化，代码更简单，逻辑更严谨
user_info = {
    'Catalog_Spri' : {'user_pwd' : 'C.Spridsb', 'times' : 0},
    'Egon' : {'user_pwd' : 'egondsb', 'times' : 0},
    'Alex' : {'user_pwd' : 'alexdsb', 'times' : 0},
}

while True:
    name = input('Please input your account>>:')
    pwd = input('Please input your password>>:')
    f = open('lock.txt', mode='r+', encoding='UTF-8')
    is_lock = f.readlines()
    if name in is_lock:
        print('Your account has been locked, please try again later.')
        break
    if name not in user_info:
        print("Your account can't be found, please try again.")
        continue
    if pwd == user_info[name]['user_pwd']:
        print('Welcome to the new world.')
        user_info[name]['times'] = 0
        break
    if pwd != user_info[name]['user_pwd']:
        user_info[name]['times'] += 1
        if user_info[name]['times'] == 3:
            f.write(name)
            print('Three times wrong, you account is locked.')
            break
        print('Your password was wrong, please try again.')
    f.close()

version 2.2
# 2.2版本增加了密码前后误加空格机制
user_info = {
    'Catalog_Spri' : {'user_pwd' : 'C.Spridsb', 'times' : 0},
    'Egon' : {'user_pwd' : 'egondsb', 'times' : 0},
    'Alex' : {'user_pwd' : 'alexdsb', 'times' : 0},
}

while True:
    name = input('Please input your account>>:')
    pwd = input('Please input your password>>:')
    f = open('lock.txt', mode='r+', encoding='UTF-8')
    is_lock = f.readlines()
    if name in is_lock:
        print('Your account has been locked, please try again later.')
        break
    if name not in user_info:
        print("Your account can't be found, please try again.")
        continue
    pwd = pwd.strip(' ')
    if pwd == user_info[name]['user_pwd']:
        print('Welcome to the new world.')
        user_info[name]['times'] = 0
        break
    if pwd != user_info[name]['user_pwd']:
        user_info[name]['times'] += 1
        if user_info[name]['times'] == 3:
            f.write(name)
            print('Three times wrong, you account is locked.')
            break
        print('Your password was wrong, please try again.')
    f.close()