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Python Code Samples

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

3 matches
Algorithms & data structures medium

Find Longest Consecutive Sequence in Python

Find the length of the longest consecutive elements sequence in an unsorted array using a set for O(n) lookups.

set longest-sequence hash-table
Python
def longest_consecutive_length(nums):
    num_set = set(nums)
    longest = 0
    
    for num in num_set:
        if num - 1 not in num_set:
            current = num
            current_streak = 1
            
            while current + 1 in num_set:
                current += 1
                current_streak += 1
…
13 0 Open
Algorithms & data structures medium

Find Longest Increasing Subsequence Length in Python

Compute the length of the longest increasing subsequence in an array using dynamic programming.

dynamic-programming subsequence algorithm
Python
def longest_increasing_subsequence(nums):
    if not nums:
        return 0
    
    dp = [1] * len(nums)
    
    for i in range(1, len(nums)):
        for j in range(i):
            if nums[i] > nums[j]:
                dp[i] = max(dp[i], dp[j] + 1)
    
    return max(dp)

if __name__ == "__main__":
    # Demo with…
15 0 Open
Concurrency & performance medium

How to Use ProcessPoolExecutor for CPU Parallel Map in Python

Run a function over a sequence of inputs in parallel across multiple CPU cores with ProcessPoolExecutor.map.

concurrency processpoolexecutor parallelism
Python
from concurrent.futures import ProcessPoolExecutor
import math

def compute_square(num):
    return num * num

def is_prime(n):
    if n < 2:
        return False
    for i in range(2, int(math.sqrt(n)) + 1):
        if n % i == 0:
            return False
    return True

if __name__ == "__main__":
    numbers = rang…
11 0 Open

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PythonSkillset code samples are short, focused examples organised by topic and difficulty. Every snippet is server-rendered HTML — readable by search engines and easy to copy. Open any sample, read the notes, copy the code, then press Try in editor to run it in the browser with Pyodide.

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