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Python Code Samples

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

4 matches
Algorithms & data structures medium

How to Find the Next Greater Element for Each List Item in Python

Use a monotonic stack to find the next greater element to the right for every item in a list, in O(n) time.

stack monotonic stack algorithm
Python
def next_greater_element(nums):
    result = [-1] * len(nums)
    stack = []
    
    for i in range(len(nums) - 1, -1, -1):
        while stack and stack[-1] <= nums[i]:
            stack.pop()
        result[i] = stack[-1] if stack else -1
        stack.append(nums[i])
    
    return result


if __name__ == "__main…
13 0 Open
Algorithms & data structures medium

How to Find the Previous Smaller Element in Python

Use a monotonic stack to find the nearest smaller element to the left of each item in a list, returning -1 when none exists.

monotonic stack stack arrays
Python
from collections import deque

def previous_smaller_elements(arr):
    stack = deque()
    result = [-1] * len(arr)

    for i in range(len(arr)):
        while stack and arr[stack[-1]] >= arr[i]:
            stack.pop()
        if stack:
            result[i] = arr[stack[-1]]
        stack.append(i)

    return resul…
15 0 Open
Algorithms & data structures medium

How to Solve Daily Temperatures Days Until Warmer in Python

Compute the number of days until a warmer temperature for each day using a monotonic stack.

stack monotonic algorithm
Python
def daily_temperatures(temps):
    n = len(temps)
    result = [0] * n
    stack = []
    
    for i, temp in enumerate(temps):
        while stack and temps[stack[-1]] < temp:
            prev_idx = stack.pop()
            result[prev_idx] = i - prev_idx
        stack.append(i)
    
    return result

if __name__ == …
12 0 Open
Algorithms & data structures medium

How to solve the stock span problem in Python

Calculate the stock span for each day's price using a monotonic stack in O(n) time.

stack monotonic-stack algorithm
Python
def stock_span(prices):
    span = [1] * len(prices)
    stack = []
    
    for i in range(len(prices)):
        while stack and prices[stack[-1]] <= prices[i]:
            stack.pop()
        span[i] = i - stack[-1] if stack else i + 1
        stack.append(i)
    
    return span

if __name__ == "__main__":
    pric…
13 0 Open

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Copy-ready Python snippets for learners and developers

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.

How to use this library

  1. Pick a topic section — strings, lists, files, functions, and more
  2. Open a sample, read How it works, and copy the code block
  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

Samples vs tutorials and challenges

Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.