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Classic patterns — search, sort, stacks, queues, and practical complexity-aware code.

3 matches

How to Combine filter and map with a List Comprehension in Python

This Python code demonstrates how to combine filtering and mapping in a single list comprehension and shows the equivalent filter() and map() approach.

list-comprehension filter map

Python

def square(x):
    return x * x

def is_even(x):
    return x % 2 == 0

numbers = [1, 2, 3, 4, 5, 6, 7, 8]

result = [square(x) for x in numbers if is_even(x)]

print(f"Original numbers: {numbers}")
print(f"Squares of even numbers: {result}")

# Combined filter + map equivalent
filtered = filter(is_even, numbers)
mapp…

13 0 Open

Algorithms & data structures easy

Split a String into Multiple Lines by Width in Python

Demonstrates a word-wrap algorithm that splits a message into rows without exceeding a maximum width.

strings word-wrap algorithm

Python

def split_message(text, max_width):
    words = text.split()
    rows = []
    current_row = []

    for word in words:
        if len(" ".join(current_row + [word])) > max_width:
            rows.append(" ".join(current_row))
            current_row = [word]
        else:
            current_row.append(word)

    if …

14 0 Open

Algorithms & data structures easy

Stable sort preserving equal order demo in Python

Demonstrates Python's stable sort, showing that elements with equal sort keys retain their original relative order.

sorting stable sort timsort

Python

from operator import itemgetter

def stable_sort_demo():
    data = [(3, "first"), (1, "second"), (3, "third"), (1, "fourth"), (2, "fifth")]
    print("Original:", data)
    
    # Sort by first element (the tuple's first value), keeping relative order of equal items
    sorted_data = sorted(data, key=itemgetter(0))
 …

13 0 Open

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