Question

关于迭代有很多答案，但是我没有找到想要的东西。因此，情况如下：我有2个2种不同长度的清单。但是l1只能是<= l2

l1 = [2, 3, 1, 2, 2]
l2 = [12, 4, 5, 2, 9, 33, 5, 8, 4, 5, 1, 7, 3]
l3 = []

我想写一个返回的函数：

l3 = [(l2[0] + l2[1], l2[2] + l2[3] + l2[4], l2[5], l3[6] + l3[7]...)]

所以

if l1[0] == 2:
Add the value of the sum of (the 2 first values of l2) in l3
if l1[0] == 3:
Add the value of the sum of (the next 3 values of l2) in l3

我尝试过：

i = 0
for v in l1:
    for k in l2:
        sum(l2[i])
    i += 1

但是，是行不通的。谢谢！

Answer 1

l1 = [2, 3, 1, 2, 2]
l2 = [12, 4, 5, 2, 9, 33, 5, 8, 4, 5, 1, 7, 3]
l3 = []

assert (len(l2) >= sum(l1))

i = 0
for e in l1:
    l3.append(sum(l2[i:i+e]))
    i += e

print (l3)
# [16, 16, 33, 13, 9]

根据python中另一个元素的元素迭代一个列表

1 个答案: