🔒 How do i fix this ?

[hybrid kayak]

ef sum_nested_list(lst1):
    sum=0
    for elem in lst1:
        if type(elem)==list:
            sum+=sum_nested_list(elem)
        if type(elem)==str:
         sum+=0
        else:
            sum+=elem
    return sum


print(sum_nested_list([1, 2, [-3, -4.5], 'abc', [5, 'abc', [-4, 0.5]]]))

[spiral willow]

@hybrid kayak

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[coarse wolf]

!e

def sum_nested_list(lst1):
    sum=0
    for elem in lst1:
        print(elem)
        if type(elem)==list:
            sum+=sum_nested_list(elem)
        if type(elem)==str:
         sum+=0
        else:
            sum+=elem
    return sum


print(sum_nested_list([1, 2, [-3, -4.5], 'abc', [5, 'abc', [-4, 0.5]]]))

[spiral willow]

@coarse wolf :x: Your 3.12 eval job has completed with return code 1.

001 | 1
002 | 2
003 | [-3, -4.5]
004 | -3
005 | -4.5
006 | Traceback (most recent call last):
007 |   File "/home/main.py", line 14, in <module>
008 |     print(sum_nested_list([1, 2, [-3, -4.5], 'abc', [5, 'abc', [-4, 0.5]]]))
009 |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
010 |   File "/home/main.py", line 10, in sum_nested_list
011 |     sum+=elem
... (truncated - too many lines)

Full output: https://paste.pythondiscord.com/DVMZIRXA3F23E2MPRZYKHWAX44

[hybrid kayak]

Huh

[silver totem]

the problem is the you call the function again at ```py
sum+=sum_nested_list(elem)

but after that returns you still check ```py
        if type(elem)==str:
         sum+=0
        else:
            sum+=elem

and ```py
sum+=elem

is runed with the list

change ```py
if type(elem)==str:

to: ```py
elif type(elem)==str:

also there are some stuff to make you code look better and probably faster

are you interested in it?

[hybrid kayak]

Go ahead im always interested

[silver totem]

firstly make the tabbing consistent throughtout the code:

        if type(elem)==list:
            sum+=sum_nested_list(elem)
        elif type(elem)==str:
            sum+=0
        else:
            sum+=elem

then you could do isinstance(elem,list) instead of type == list (you also could do it with any datatype)

don't name your variables to and already existing function (like sum)

instead of ```py
elif type(elem)==str:
sum+=0

you could do: ```py
        elif type(elem)==str:
            continue

(continue makes the for cycle step to the next iteration without running anything after continue)

[haughty kraken]

Or just you could skip the mayhem

def flatten(S):
    """Flatten a list recursively to a 1-D list

    https://stackoverflow.com/a/12472564
    """
    if S == []:
        return S
    if isinstance(S[0], list):
        return flatten(S[0]) + flatten(S[1:])
    return S[:1] + flatten(S[1:])


def sum_nested_list(lst1):
    return sum(i for i in flatten(lst1) if not isinstance(i, str))

Pinch code from StackOverflow, step 1 to be a programmer

[vague elk]

You can also do a lil functional programming

def sum_nested_list(l: list):
    result = 0
    result += sum(n for n in l if type(n)==int)
    result += sum(sum_nested_list(t) for t in l if type(t)==list)
    return result

[hybrid kayak]

Lol

[silver totem]

why typehint the input and not typehint the output?

[hybrid kayak]

Can you explain what you did here

[vague elk]

Something like pylance will catch that this returns an int, but it won't know that l is a list if you don't type hint that

[vague elk]

n for n in l if type(n)==int gives you all the ints in the current list, and we sum that
t for t in l if type(t)==list gives you all the lists, so we want to add together all the sum_nested_list(t)

[silver totem]

wow I didn't know that one

[hybrid kayak]

Oh so u didn't use recursion at all

[vague elk]

No I did, here

def sum_nested_list(l: list):
    result = 0
    result += sum(n for n in l if type(n)==int)
    result += sum(sum_nested_list(t) for t in l if type(t)==list) # <--
    return result

[hybrid kayak]

Oh i see

[coarse wolf]

https://www.w3schools.com/python/python_lists_comprehension.asp
check out list comprehension if you dont know whats going on

newlist = [expression for item in iterable if condition == True]

[tacit rock]

!e
you could also use an accumulator:

def nested_sum(lst, acc=0):
    if not lst:
        return acc
    if isinstance(lst[0], list):
        acc += nested_sum(lst[0])
    if isinstance(lst[0], int):
        acc += lst[0]
    return nested_sum(lst[1:], acc)

print(nested_sum([1,2, [2,3, "test",4], "a", [4, "kl", 5], 2, [5, "hj", 7, [6, 9, [1, 2]]]]))

[spiral willow]

@tacit rock :white_check_mark: Your 3.12 eval job has completed with return code 0.

53

[spiral willow]

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