作业练习

#:/usr/bin/env python 
# # -*- coding:utf-8 -*-
usernames = ['xiaohei','xiaobai','xiaoming']
passwords = ['123456','11111','1']
#print(dict(zip(usernames,passwords)))

user_info={}
for i in range(len(usernames)):
     user_info[usernames[i]]=passwords[i]
for i in range(3):
    user = input('请输入账号')
    pwd = input('请输入密码')
    again_pwd =input('请再次输入密码')
    if user in usernames:
        print('用户名已被注册')
    elif again_pwd != pwd:
        print('密码不一样')
    elif  user == ' 'or pwd == ' 'or again_pwd == ' ':
        print('用户名密码不能为空')
    if pwd ==again_pwd:
        print('注册成功')
    # user_info[user]=pwd
        user_info.setdefault(user,pwd)
        print(user_info)
    #continue
print('次数超限')

登录

#:/usr/bin/env python
# # -*- coding:utf-8 -*-
usernames = ['xiaohei','xiaobai','xiaoming']
passwords = ['123456','11111','1']
#print(dict(zip(usernames,passwords)))
user_info={}
for i in range(len(usernames)):
     user_info[usernames[i]]=passwords[i]
for i in range(3):
    user = input('请输入账号')
    pwd = input('请输入密码')
    if user =='' or ''.isspace():   #方法检测字符串是否只由空格组成
        print ('账号不能为空')
        continue
    elif pwd ==''or pwd.isspace():
        print('请重新输入')
        continue
    # else:
    #     print('请输入正确的账户')
    if user_info.get(user): #字典中查找的值
        if user_info[user] == pwd:
            print('登录成功')
            break
        else:
            print('密码错误')
            continue
    else:
        print('账号未注册')