python中的单个列表添加

如果我有这些清单：

a = [1,2,3]
b = [4,5,6]

如何通过列表b中的all添加列表a中的每个元素

final_list = [5,6,7,6,7,8,7,8,9]

我尝试过使用2 for循环，但作为一个业余爱好者，我认为有一种更有效的方法。干杯

您可以使用计算

a

和

b

的笛卡尔积，然后计算每对的积/和：

>>> import itertools
>>> a = [1,2,3];b = [4,5,6]
>>> list(itertools.product(a,b)) # This step isn't needed. It's just to show the result of itertools.product
[(1, 4), (1, 5), (1, 6), (2, 4), (2, 5), (2, 6), (3, 4), (3, 5), (3, 6)]
>>> [i + j for i, j in itertools.product(a, b)]
[5, 6, 7, 6, 7, 8, 7, 8, 9]
>>> [i * j for i, j in itertools.product(a, b)]
[4, 5, 6, 8, 10, 12, 12, 15, 18]

简单地

[4,5,6,8,10,12,12,15,18]

[5,6,7,6,7,8,7,8,9]

---

你也可以像前面的答案一样做加法

>>> [i+j for i in a for j in b]
[5, 6, 7, 6, 7, 8, 7, 8, 9]

---

处理n个列表怎么样

from itertools import product

def listSum(lists):
  return [sum(list) for list in product(*lists)]

print(listSum(([1,2,3],[4,5,6]))) #=> [5, 6, 7, 6, 7, 8, 7, 8, 9]
print(listSum(([1,2,3], ))) #=> [1, 2, 3]
print(listSum(([1,2,3],[4,5,6],[7,8,9]))) #=> [12, 13, 14, 13, 14, 15, 14, 15, 16, 13, 14, 15, 14, 15, 16, 15, 16, 17, 14, 15, 16, 15, 16, 17, 16, 17, 18]

---

请展示你的努力，我没有想到。为什么不使用

sum

而不是

reduce（lambda x，y:x+y，list，0）

？在最初的问题中，他要求的是乘积而不是总和。。。。因此，在编辑时，我使用了相同的逻辑，但可以简化

>>> [i+j for i in a for j in b]
[5, 6, 7, 6, 7, 8, 7, 8, 9]

from itertools import product

def listSum(lists):
  return [sum(list) for list in product(*lists)]

print(listSum(([1,2,3],[4,5,6]))) #=> [5, 6, 7, 6, 7, 8, 7, 8, 9]
print(listSum(([1,2,3], ))) #=> [1, 2, 3]
print(listSum(([1,2,3],[4,5,6],[7,8,9]))) #=> [12, 13, 14, 13, 14, 15, 14, 15, 16, 13, 14, 15, 14, 15, 16, 15, 16, 17, 14, 15, 16, 15, 16, 17, 16, 17, 18]