一、元素分类

有如下值集合 [11,22,33,44,55,66,77,88,99,90...]，将所有大于 66 的值保存至字典的第一个key中，将小于 66 的值保存至第二个key的值中。

即： {‘k1‘: 大于66的所有值, ‘k2‘: 小于66的所有值}

li1 = [11, 22, 33, 44, 55, 66, 77, 88, 99, 90]
dic1 = {‘high66‘: [], ‘low66‘: []}
for i1 in li1:
    if i1 > 66:
        dic1[‘high66‘].append(i1)
    elif i1 < 66:
        dic1[‘low66‘].append(i1)
print(dic1)

二、查找

查找列表中元素，移除每个元素的空格，并查找以 a或A开头 并且以 c 结尾的所有元素。

    li = ["alec", " aric", "Alex", "Tony", "rain"]

    tu = ("alec", " aric", "Alex", "Tony", "rain")

    dic = {‘k1‘: "alex", ‘k2‘: ‘ aric‘,  "k3": "Alex", "k4": "Tony"}

dic2 = {‘k1‘: ‘alec‘, ‘k2‘: ‘Aric‘, ‘k3‘: ‘Alex‘, ‘k4‘: ‘Tony‘}
for dic2_1 in dic2:
    if (dic2[dic2_1].startswith(‘a‘) or dic2[dic2_1].startswith(‘A‘)) and dic2[dic2_1].endswith(‘c‘):
        print(dic2_1, dic2[dic2_1])

三、输出商品列表，用户输入序号，显示用户选中的商品

    商品 li = ["手机", "电脑", ‘鼠标垫‘, ‘游艇‘]

 li3 = [‘手机‘, ‘电脑‘, ‘鼠标垫‘, ‘游艇‘]
for li3_1 in enumerate(li3):
    print(li3_1)
choice3_inp = input(‘请输入你要选择的商品序号(0-3):‘)
choice3_inp = int(choice3_inp)
print(li3[choice3_inp])

四、购物车

功能要求：

要求用户输入总资产，例如：2000

显示商品列表，让用户根据序号选择商品，加入购物车

购买，如果商品总额大于总资产，提示账户余额不足，否则，购买成功。

附加：可充值、某商品移除购物车

goods = [

    {"name": "电脑", "price": 1999},

    {"name": "鼠标", "price": 10},

    {"name": "游艇", "price": 20},

    {"name": "美女", "price": 998},

]

goods = [  # 购物车以商品清单为基础，增加一个表示商品数量的键值对
    {"name": "电脑", "price": 1999, "num": 0},
    {"name": "鼠标", "price": 10, "num": 0},
    {"name": "游艇", "price": 20, "num": 0},
    {"name": "美女", "price": 998, "num": 0},
]
wallet = 0
tag4 = True
while tag4:
    choice4_inp = input(‘你的余额是%s元，请选择：1、充值 2、购物 3、结算 ‘ % (wallet))
    if choice4_inp == ‘1‘:  # 第一个选项是充值
        charge_inp = int(input(‘请输入充值的金额：‘))
        wallet = wallet + charge_inp
        print(‘充值成功‘)
    elif choice4_inp == ‘2‘:  # 第二个选项是商品购买
        while True:
            for li4_1 in enumerate(goods, 1):
                print(li4_1)
            buy_inp = input(‘请输入你要购买的商品(输入q返回，输入c修改购物车)：‘)
            if buy_inp == ‘q‘:
                break
            elif buy_inp == ‘c‘:    # 清空购物车
                while True:
                    for shopping_car_1 in enumerate(goods, 1):
                        print(shopping_car_1)
                    car_inp = input(‘清空商品请输入对应序号（输入q返回上一菜单）：‘)
                    if car_inp == ‘q‘:
                        break
                    car_inp = int(car_inp) - 1
                    goods[car_inp][‘num‘] = 0
            elif buy_inp.isdigit(): # ，购买成功，对应商品的num加一
                buy_inp = int(buy_inp) - 1
                goods[buy_inp][‘num‘] += 1
                print(‘商品加入购物车！‘)
            else:
                print(‘输入错误，请重新输入‘)
    elif choice4_inp == ‘3‘:  # 第三个选项是结算，余额>=账单则购买成功
        bill = 0
        for pay in range(0, len(goods)):
            bill = bill + goods[pay][‘price‘] * goods[pay][‘num‘]
        wallet = wallet - bill
        if wallet >= 0:
            print(‘购物完成，你消费了共%s元，余额%s元‘ % (bill, wallet))
            print(‘**购物清单**‘)
            for ending in goods:
                if ending[‘num‘] > 0:
                    print(ending[‘name‘], ending[‘num‘])
        else:
            print(‘穷逼，88！‘)
        tag4 = False