知识点： 文件读，写操作，if 判断， for 循环
salary = input("输入你的工资：")
bought_list = []
product_list = {}
with open("product_list","r",encoding="utf-8") as f1:
for item in f1:
p_name,p_price = item.strip().split(':')
product_list[p_name]=int(p_price)
print(product_list)
if salary.isdigit():
salary = int(salary)
while True:
user_choice = input("please input product which you want:")
if user_choice in product_list.keys():
if product_list[user_choice] <= salary:
bought_list.append(user_choice) #增加列表的元素
salary = salary - product_list[user_choice]
print("Had bought [\033[32;1m%s\033[0m], and your balance is \033[31;1m%s\033[0m"%(user_choice,salary))
print(bought_list)
else:
print("Your balance is less than product's price")
continue
elif user_choice is 'q':
with open('bought.txt','w+',encoding='utf-8') as f2:
for goods in bought_list:
print(goods,file=f2)
exit(print("You had bought %s goods, and your balance is %s"%(bought_list, salary)))
else:
print("The good had been sold out")测试：
输入你的工资：15000
{'Python': 20, 'Iphone': 5288, 'Iwatch': 3288, 'Bike': 2400, 'Mac pro': 12888}
please input product which you want:Python
Had bought [Python], and your balance is 14980
['Python']
please input product which you want:Bike
Had bought [Bike], and your balance is 12580
['Python', 'Bike']
please input product which you want:Mac pro
Your balance is less than product's price
please input product which you want:Iwatch
Had bought [Iwatch], and your balance is 9292
['Python', 'Bike', 'Iwatch']
please input product which you want:q
You had bought ['Python', 'Bike', 'Iwatch'] goods, and your balance is 9292 
