Python多循环

Question

A = [[[1,2,3],[4]],[[1,4],[2,3]]]

在这里，我要查找A中的列表，列表中所有子列表的总和不大于5。

结果应该是[[1,4],[2,3]]

我花了很长时间解决python中的这个问题。 但是我仍然想不出正确的解决方案，我坚持将其循环出多个循环。 我的代码如下，但其明显错误，如何纠正？

A = [[[1,2,3],[4]],[[1,4],[2,3]]]
z = []
for l in A:
    for list in l:
        sum = 0
        while sum < 5:
            for i in list:
                sum+=i
        else:
            break
    else:
        z.append(l)
print z

寻求帮助〜

Answer 1

单行式@KindStranger方法的简化：

>> [sub for x in A for sub in x if max(sum(sub) for sub in x) <= 5]
[[1, 4], [2, 3]]

Answer 2

这应该可以解决您的问题：

>>> for alist in A:
...     if max(sum(sublist) for sublist in alist) <= 5:
...         print(alist)
...
[[1, 4], [2, 3]]

Answer 3

您可以想到的一个简单的解决方案是这样的-

A = [[[1,2,3],[4]],[[1,4],[2,3]]]

r = []   # this will be our result

for list in A:  # Iterate through each item in A
    f = True    # This is a flag we set for a favorable sublist
    for item in list:  # Here we iterate through each list in the sublist
        if sum(item) > 5:  # If the sum is greater than 5 in any of them, set flag to false
            f = False
    if f:       # If the flag is set, it means this is a favorable sublist
        r.append(list)

print r

但是我假设嵌套级别是相同的。 http://ideone.com/hhr9uq

Answer 4

与all()

[t for item in A for t in item if all(sum(t)<=5 for t in item)]