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Python Code Samples

Easy snippets you can copy, study, and run in the browser editor.

2 matches
Algorithms & data structures easy

Find Common Elements in List of Lists in Python

Return elements that appear in every sublist of a nested list, preserving duplicates with Counter intersection.

counter intersection nested-lists
Python
from collections import Counter


def common_elements(list_of_lists):
    """Return elements present in every sublist."""
    if not list_of_lists:
        return []
    counts = Counter(list_of_lists[0])
    for sublist in list_of_lists[1:]:
        counts &= Counter(sublist)
    return list(counts.elements())


if _…
13 0 Open
Comprehensions & generators easy

Flatten a Nested List in Python (Recursive Generator)

Recursively flatten arbitrarily nested lists into a single-level list using both a function and a generator with `yield from`.

recursion generators flatten
Python
def flatten(nested_list):
    """Recursively flatten a nested list into a single-level list."""
    result = []
    for item in nested_list:
        if isinstance(item, list):
            result.extend(flatten(item))
        else:
            result.append(item)
    return result


def flatten_generator(nested_list):
…
14 0 Open

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