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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

3 matches
Algorithms & data structures easy

Extract n largest elements from a large list using heapq

Uses heapq.nlargest to efficiently extract the top n largest numbers from a large list, even with millions of elements.

heapq heaps large-data
Python
import heapq
import random

def n_largest(numbers, n):
    """Return the n largest numbers from a list using heapq."""
    if n <= 0:
        return []
    return heapq.nlargest(n, numbers)

if __name__ == "__main__":
    # Create a large list with 1,000,000 random numbers
    large_list = [random.randint(1, 1_000_000…
14 0 Open
Algorithms & data structures medium

How to Find the n Smallest Items in a Large List with heapq in Python

This code demonstrates how to efficiently extract the n smallest items from a large list using Python's heapq module and a manual max-heap approach.

heapq heaps large data
Python
import heapq

def n_smallest_iterable(data, n):
    """Return the n smallest items without loading the whole list."""
    if n <= 0:
        return []
    return heapq.nsmallest(n, data)

def n_smallest_manual(data, n):
    """Return the n smallest using a heap, O(n log k) time."""
    if n <= 0:
        return []
   …
13 0 Open
Data pipelines & processing medium

Deduplicate events by ID within a window in Python

Deduplicate event streams by ID within sliding time windows, keeping the newest occurrence per window using heaps and sets.

deduplication events heapq
Python
import heapq
from collections import defaultdict

def deduplicate_events(events, window_size):
    """Return events deduplicated by id, keeping newest within each sliding window."""
    # Index events by (timestamp, id) for deterministic ordering
    events_by_id = defaultdict(list)
    for ts, eid, *payload in events…
14 0 Open

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