有没有办法在python中压缩列表/元组的内部元素？

Question

我遇到了一个简单的python问题，要解决：拥有3类商品及其对应值的列表，在3个列表中打印出总价值低于X的所有组合。（代码示例可能更清楚地说明）。

我设法使用zip（）和itertools.product（）创建了组合，但要输出正确的组合，我觉得必须有一种更好的，更Python化的方式来表达输出通过压缩产品的内部元组来获得价格的总和，而无需创建2个明确的生成器/列表（我相信这种情况下用例并不重要）。来自Java的背景，有时我仍然遇到一些问题，有时无法陷入类似于Java的语法中，这是我绝对希望在Python中避免的问题。

这是我的代码：

import itertools

# Print out all possible meal combinations under $30

main_courses = ['beef stew', 'fried fish']
price_main_courses = [28, 23]

desserts = ['ice-cream', 'cake']
price_desserts = [2, 4]

drinks = ['cola', 'wine']
price_drinks = [3, 10]

products = itertools.product(
    zip(main_courses, price_main_courses),
    zip(desserts, price_desserts),
    zip(drinks, price_drinks)
)

for combo in products:
    names = (x[0] for x in combo)
    price = sum((x[1] for x in combo))
    if price <= 30:
        print(*names, price)

Answer 1

基于this，for循环可写为：

for combo in products:
    names, prices = zip(*combo)
    price = sum(prices)
    if price <= 30:
        print(*names, price)

Answer 2

嗯，我唯一要做的就是使用列表推导而不是for循环，例如：

import itertools

# Print out all possible meal combinations under $30

main_courses = ['beef stew', 'fried fish']
price_main_courses = [28, 23]

desserts = ['ice-cream', 'cake']
price_desserts = [2, 4]

drinks = ['cola', 'wine']
price_drinks = [3, 10]

products = itertools.product(
    zip(main_courses, price_main_courses),
    zip(desserts, price_desserts),
    zip(drinks, price_drinks)
)

combos = [
    combo for combo in products if sum(price for name, price in combo) <= 30
]

for combo in combos:
    print(' + '.join(name for name, price in combo), '=', sum(price for name, price in combo))

>>> "fried fish + ice-cream + cola = 28"
>>> "fried fish + cake + cola = 30"