1,用户先给自己的账户充钱：比如先充3000元。
2,有如下的一个格式:
goods = [{"name": "电脑", "price": 1999},
{"name": "鼠标", "price": 10},
{"name": "游艇", "price": 20},
{"name": "美女", "price": 998},]3,页面显示 序号 + 商品名称 + 商品价格，如：
1 电脑 1999
2 鼠标 10
…
4,用户输入选择的商品序号，然后打印商品名称及商品价格,并将此商品，添加到购物车(自己定义购物车)，用户还可继续添加商品。
5,如果用户输入的商品序号有误，则提示输入有误，并重新输入。
6,用户输入N为购物车结算，依次显示用户购物车里面的商品，数量及单价，若充值的钱数不足，则让用户删除某商品，直至可以购买，若充值的钱数充足，则可以直接购买。
7,用户输入Q或者q退出程序。
8,退出程序之后，依次显示用户购买的商品，数量，单价，以及此次共消费多少钱，账户余额多少，并将购买信息显示。
麻烦算法：
goods = [{"name": "电脑", "price": 1999},
{"name": "鼠标", "price": 10},
{"name": "游艇", "price": 20},
{"name": "美女", "price": 998}, ]
shop_car = {}
while 1:
try:
m = int(input("请输入充钱金额>>>"))
count = 0
for i in goods:
count += 1
print(count, i["name"], i["price"])
while 1:
cho_goods = input("买点东西啊小老弟>>>")
try:
cho_goods = int(cho_goods)
a = (goods[cho_goods - 1]["name"], goods[cho_goods - 1]["price"])
if a in shop_car:
shop_car[a] += 1
else:
shop_car[a] = 1
except ValueError:
if cho_goods.upper() == "N":
while 1:
pay_money = 0
for i in range(len(shop_car)):
name = list(shop_car.keys())[i][0]
price = list(shop_car.keys())[i][1]
twice = list(shop_car.values())[i]
pay_money += price * twice
print(f'商品名称：{name} 商品单价:{price} 购买数量:{twice}')
if pay_money > m:
msg = input("超额了熬！！删点什么吧")
shop_car1 = shop_car.copy()
for k in shop_car1:
if msg == k[0]:
shop_car[k] -= 1
if shop_car[k] == 0:
del shop_car[k]
else:
pay_money = 0
print("—————————购买成功—————————")
for i in range(len(shop_car)):
name = list(shop_car.keys())[i][0]
price = list(shop_car.keys())[i][1]
twice = list(shop_car.values())[i]
pay_money += price * twice
print(f'商品名称：{name} 商品单价:{price} 购买数量:{twice}')
print(f"总共花费：{pay_money}")
print(f"钱包余额：{m-pay_money}")
print("————————欢迎下次光临————————")
exit()
elif cho_goods.upper() == "Q":
print("欢迎下次光临！")
exit()
else:
print("请重新输入！")
except IndexError:
print("请重新输入")
except ValueError:
print("你这钱也不是个正经钱啊！")简单算法：
goods = [{"name": "电脑", "price": 1999},
{"name": "鼠标", "price": 10},
{"name": "游艇", "price": 20},
{"name": "美女", "price": 998}, ]
while 1:
money = input("充点钱啊！老铁！（按Q退出）")
try:
money = int(money)
name, price, twice = [], [], []
for i in range(len(goods)):
print(i + 1, goods[i]["name"], goods[i]["price"])
name.append(goods[i]["name"])
price.append(goods[i]["price"])
twice.append(0)
while 1:
num = input("请输入你要购买的东西：")
try:
num = int(num)
twice[num - 1] += 1
print("以将{}加入购物车，单价为：{}".format(name[num - 1], price[num - 1]))
except ValueError:
if num.upper() == "N":
while 1:
pay = 0
for i in range(len(goods)):
if twice[i] <= 0:
pass
else:
print(name[i], price[i], twice[i])
pay += price[i] * twice[i]
if pay > money:
msg = input("超额了熬！！删点什么吧")
if msg.upper() == "Q":
print("欢迎下次光临！")
exit()
if msg in name:
twice[name.index(msg)] -= 1
else:
print("—————————购买成功—————————")
for i in range(len(goods)):
if twice[i] == 0:
pass
else:
print(f'商品名称：{name[i]} 商品单价:{price[i]} 购买数量:{twice[i]}')
print(f"总共花费：{pay}")
print(f"钱包余额：{money-pay}")
print("————————欢迎下次光临————————")
exit()
elif num.upper() == "Q":
print("欢迎下次光临！")
exit()
else:
print("请重新输入！")
except IndexError:
print("请重新输入")
except ValueError:
if money.upper() == "Q":
print("欢迎下次光临！")
exit()
else:
print("你这钱也不是个正经钱啊！")
原文：https://www.cnblogs.com/jevious/p/11190299.html