python基础练习题

购物车程序

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Time    : 2018/3/6 21:01
# @Author  : hyang
# @Site    :
# @File    : shop_cart.py
# @Software: PyCharm

"""
购物车程序
数据结构：
goods = [
{"name": "电脑", "price": 1999},
{"name": "鼠标", "price": 10},
{"name": "游艇", "price": 20},
{"name": "美女", "price": 998},
......
]

功能要求：
基础要求：

1、启动程序后，输入用户名密码后，让用户输入工资，然后打印商品列表

2、允许用户根据商品编号购买商品

3、用户选择商品后，检测余额是否够，够就直接扣款，不够就提醒

4、可随时退出，退出时，打印已购买商品和余额

5、在用户使用过程中， 关键输出，如余额，商品已加入购物车等消息，需高亮显示


扩展需求：

1、用户下一次登录后，输入用户名密码，直接回到上次的状态，即上次消费的余额什么的还是那些，再次登录可继续购买

2、允许查询之前的消费记录
"""
import os

# 商品列表
goods = [
    {"name": "电脑", "price": 1999},
    {"name": "鼠标", "price": 10},
    {"name": "游艇", "price": 20},
    {"name": "IPAD", "price": 1998},
    {"name": "手机", "price": 998},
    {"name": "玩具", "price": 50},
    {"name": "教科书", "price": 100}
]

last_shop = []  # 上次购买数据
last_bal = []  # 得到每次购买余额

def is_shop(user):
    """
    判断该用户是否已消费数据
    :param user:
    :return:
    """
    flg = False
    if os.path.exists(r"user_shop.txt"):
        # 查询用户有购买记录
        with open(r"user_shop.txt", "r", encoding='utf-8') as f:
            for line in f:
               if line.find(user) != -1:
                   flg = True
                   break
    else:  # 创建空文件
         with open(r"user_shop.txt", "w", encoding='utf-8') as f:
             f.write("")
    return flg


def login():
    """
    用户登录
    :return:
    """
    err_cnt = 0
    suc_user = ''  # 返回成功登录用户
    # 判断锁标志
    while err_cnt < 3:
        user = input('输入用户名: ')
        pwd = input('输入密码: ')
        if user == 'alex' and pwd == '123':
            print('登录成功')
            suc_user = user
            break
        else:
            print('登录失败')
        err_cnt += 1
    else:
        print('您登录失败已超过3次')
    return suc_user


def check_salary():
    """
    检查收入
    :return:
    """
    while True:
        salary = input('输入工资: ')
        if salary.isdigit():
            break
        else:
            print('工资输入错误，请重新输入！')
    return int(salary)


def shop(user, salary):
    """
    用户购物
    """
    shop_cart = []  # 购物车
    while True:
        print('-------商品列表--------')
        for index, value in enumerate(goods):
            print('商品编号:%s   商品名称:%s   商品价格:%s' % (index, value['name'], value['price']))

        choice = input('输入商品编号:---输入q退出购买 ')
        if choice.isdigit():
            choice = int(choice)
            if 0 <= choice < len(goods):
                price = goods[choice]['price']
                if (salary - price) > 0:
                    salary = salary - price
                    shop_cart.append(goods[choice])
                    print('33[1;32;40m购买商品编号:%s   购买商品名称:%s   购买商品价格:%s33[0m'
                          % (choice, goods[choice]['name'], goods[choice]['price']))
                    print('33[1;32;40m工资余额=%s33[0m' % salary)
                else:
                    print('余额不足')
                    continue
            else:
                print('商品编号不存在！')

        elif choice == 'q':
            print('33[1;31;40m-------本次购物退出--------33[0m')
            if len(shop_cart) > 0:
                print('-------本次购买商品列表--------')
                with open(r"user_shop.txt", "a+", encoding='utf-8') as f:
                    f.write("user:%s
" % user)
                    for value in shop_cart:
                        shop_info = '购买商品名称:%s|购买商品价格:%s' % (value['name'], value['price'])
                        print('33[1;32;40m%s33[0m' % shop_info)
                        f.write(shop_info + "
")
                    bal_info = '工资余额:%s' % salary
                    print('33[1;32;40m%s33[0m'% bal_info)
                    f.write(bal_info + "
")
            break

def get_shop(user):
    """
    读取文件得到用户已消费数据
    :param user:
    :return:
    """
    flg = False
    resume_goods = []  # 消费商品
    with open(r"user_shop.txt", "r", encoding='utf-8') as f:
        for line in f:
            if line.find("购买") != -1:
                shop_li = line.split("|")
                resume_goods.append([shop_li[0].split(":")[1].strip(), shop_li[1].split(":")[1].strip()])
            elif line.find("余额") != -1:
                last_bal.append(line.split(":")[1].strip())
        print("33[1;32;40m历史购物:%s33[0m" % resume_goods)  # 带绿色输出
        print('33[1;32;40m还剩下余额:%s33[0m' % last_bal[-1]) # 带绿色输出


if __name__ == '__main__':
    user = login()
    if user != '':
        print('{}登录成功'.format(user))
        while True:
            action = input('输入c查询消费记录，输入b购买商品,输入q退出：')
            if action == 'q':
                print('33[1;31;40m---退出程序------33[0m')  # 带红色输出
                get_shop(user)
                break
            elif action == 'c':
                if is_shop(user):
                    print("---查询之前的消费记录---")
                    get_shop(user)
                else:
                    print("---查询之前无消费记录---")
            elif action == 'b':
                if not is_shop(user):
                    salary = check_salary()
                else:
                    salary = int(last_bal[-1])
                print('您工资现有:', salary)
                shop(user, salary)

输出结果

三级菜单程序

#!/usr/bin/env python3 
# -*- coding: utf-8 -*-
# @Time    : 2018/3/1 9:38
# @Author  : hyang
# @File    : three_menu.py
# @Software: PyCharm
"""
可依次选择进入各子菜单
可从任意一层往回退到上一层
可从任意一层退出程序
"""
menu = {
    '北京':{
        '海淀':{
            '五道口':{
                'soho':{},
                '网易':{},
                'google':{}
            },
            '中关村':{
                '爱奇艺':{},
                '汽车之家':{},
                'youku':{},
            },
            '上地':{
                '百度':{},
            },
        },
        '昌平':{
            '沙河':{
                '老男孩':{},
                '北航':{},
            },
            '天通苑':{},
            '回龙观':{},
        },
        '朝阳':{},
        '东城':{},
    },
    '上海':{
        '闵行':{
            "人民广场":{
                '炸鸡店':{}
            }
        },
        '闸北':{
            '火车站':{
                '携程':{}
            }
        },
        '浦东':{},
    },
    '山东':{},
}

current_menu = menu  # 当前菜单
last_menu = []  # 上层菜单
prompt = "输入菜单名，进入子菜单
 输入'b'，返回上层菜单
 输入'q'，退出程序
"
while True:
    if len(current_menu) == 0:
        print('已经到最底层，该菜单下无节点')
    else:
        for k in current_menu:
            print('菜单->', k)
    input_str = input(prompt).strip()
    if input_str == 'q':
        print('退出程序')
        break
    elif input_str in current_menu:
        last_menu.append(current_menu)  # 保存上一层菜单
        current_menu = current_menu[input_str]  # 保存当前层
    elif input_str == 'b':
        if len(last_menu) != 0:
            current_menu = last_menu.pop()  # 弹出上一层菜单
        else:
            print('已经是顶层菜单')
    else:
        print('该节点菜单不存在')
        continue