将字典中的值一起添加

Question

我正在为我的大学班级创建一个程序，将商品添加到购物车并显示总价格和数量。这是我的示例代码。之后我会将这些信息传输到一个类文件中：shop_cart = {}item_quantity = int(input('How many items? '))print()for i in range(item_quantity):    print('Item #', i+1, sep=' ')    item_name = str(input('Item Name: '))    item_price = float(input('Item Price: '))    shop_cart[item_name] = item_price    item_quantity = int(input('Item Quantity: '))    shop_cart[item_name] = item_price, item_quantity    print()print('Shopping Cart: ', shop_cart)print()    remove = str(input('Do you want to remove items? (Y/N): '))if remove == 'Y':    remove_item = int(input('How many items to remove? '))    for i in range(remove_item):        remove_name = str(input('Enter item name to be removed: '))        del shop_cart[remove_name]        print(remove_name, 'has been removed from shopping cart.')print()print('Shopping Cart: ', shop_cart)print('Checking out')我有麻烦乘以item_price通过item_quantity，然后将所有的值加在一起来创建一个“总价值”对象。

Answer 1

由于您的字典中的值是元组，您可以获取所有这些值，.values()然后使用它们sum来添加每个元组的所有产品：

print('Shopping Cart: ', shop_cart)

print('Total: ', sum(price * quantity for price, quantity in shop_cart.values()))

输出

Shopping Cart:  {'Banana': (1.0, 6), 'Apple': (2.0, 5)}                                                                                             

Total:  16.0

Answer 2

from itertools import starmap

import operator as op

total = sum(starmap(op.mul, cart.values())