Combinations in Lists of List

user_4538768 0
Viewed 64

Having the following list of lists ['boundari', 'special', ['forest', 'arb'], 'abod'], I would like to obtain the the following combination:

[['boundari', 'special', 'forest', 'abod'], ['boundari', 'special', 'arb', 'abod']]

The nearest solution applying the next product when removing the last item abod (which I need to keep):

print([list(p) for p in product([toks[:2]], *toks[2:])])

[[['boundari', 'special'], 'forest'], [['boundari', 'special'], 'arb']]

However, I have not obtained the correct combination:

 [['boundari', 'special', 'forest', 'abod'], ['boundari', 'special', 'arb', 'abod']]
list python
2 Answers

You can do something like this:

arr = ['boundari', 'special', ['forest', 'arb'], 'abod']


def get_combinations(arr):
    n = len(arr)

    def _get_combinations(so_far, idx):
        if idx >= n:
            yield so_far[:]
            return

        if isinstance(arr[idx], list):
            for val in arr[idx]:
                so_far.append(val)
                yield from _get_combinations(so_far, idx + 1)
                so_far.pop()
        else:
            so_far.append(arr[idx])
            yield from _get_combinations(so_far, idx + 1)
            so_far.pop()

    yield from _get_combinations([], 0)


expected_ans = [
    ['boundari', 'special', 'forest', 'abod'], 
    ['boundari', 'special', 'arb', 'abod'],
]
assert list(get_combinations(arr)) == expected_ans
user_50998030

Another solution using only simple loops would be something like this and in case order of lists inside is not important:

my_list_of_list = ['boundari', 'special', ['forest', 'arb'], 'abod']
indecies_of_lists = []
base_list = []
lists_of_lists = []

output = []
for item in my_list_of_list:
    if type(item) == list:
        lists_of_lists.append(item)
    else:
        base_list.append(item)

for item in lists_of_lists:
    for sub_item in item:
        new_list = list(base_list)
        new_list.append(sub_item)
        output.append(new_list)
print(output)

output will be [['boundari', 'special', 'abod', 'forest'], ['boundari', 'special', 'abod', 'arb']]

user_54627750
Related