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Comprehensions & generators

List/dict/set comprehensions, generator expressions, and lazy iteration.

5 matches

Dict Comprehension to Map Keys to Lengths in Python

Build a dictionary that maps each word to its character count using a dictionary comprehension.

words = ["apple", "banana", "cherry", "date", "elderberry"]

word_lengths = {word: len(word) for word in words}

print(word_lengths)

14 0 Open

Comprehensions & generators easy

Drop n items then yield rest generator

A generator that skips the first n items of an iterable and then yields the remaining items one by one.

generators iterators drop

Python

def drop(n, items):
    """Yield every item except the first n from items."""
    it = iter(items)
    for _ in range(n):
        next(it, None)  # skip first n items
    yield from it


if __name__ == "__main__":
    numbers = [10, 20, 30, 40, 50]
    result = list(drop(2, numbers))
    print(result)

11 0 Open

Comprehensions & generators easy

How to Generate a Collatz Sequence in Python

Generate the Collatz sequence for a given positive integer by repeatedly applying the 3n+1 rule until reaching 1.

collatz sequence loops

Python

def collatz_sequence(n):
    if n <= 0:
        raise ValueError("n must be a positive integer")
    sequence = [n]
    while n != 1:
        if n % 2 == 0:
            n = n // 2
        else:
            n = 3 * n + 1
        sequence.append(n)
    return sequence

if __name__ == "__main__":
    start = 7
    result…

14 0 Open

Comprehensions & generators easy

How to Repeat a Generator Cycle Single Value in Python

Build a generator that repeats a single value across multiple cycles, each cycle adding an extra repetition to mark its completion.

generators loops repeat

Python

def repeat_with_cycle(value, cycle_limit, repetitions):
    """
    Repeats a single value until reaching a cycle limit,
    then yields the value one more time to demonstrate a full cycle.
    
    Args:
        value: The single value to repeat.
        cycle_limit: Number of repetitions per cycle.
        repetitio…

13 0 Open

Comprehensions & generators easy

Merge Data with Comprehension and Generator in Python

Merge user and order data using a dictionary comprehension for lookups and a generator expression to filter and transform orders.

dictionary-comprehension generator-expression data-merging

Python

def merge_data(users, orders):
    """
    Merge user and order data using a dictionary comprehension
    and a generator expression for filtering.
    """
    # Build a lookup: user_id -> user name
    user_map = {user["id"]: user["name"] for user in users}

    # Generator: yield orders with user names attached
    …

14 0 Open

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