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Python Code Samples

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

2 matches
Dictionaries & sets easy

How to Sort Dictionary Keys Alphabetically in Python

This code returns a list of dictionary keys sorted alphabetically, using a case-insensitive comparison while preserving the original insertion order for keys that are equal.

sorting dictionary case-insensitive
Python
data = {
    "banana": 3,
    "apple": 1,
    "Cherry": 5,
    "date": 2,
    "apple": 4,
    "Fig": 6,
    "banana": 2,
}

def sort_dict_keys_alphabetically(d):
    """Return a list of keys sorted alphabetically (case-insensitive), stable for duplicates."""
    return sorted(d.keys(), key=lambda k: k.lower())

if __n…
11 0 Open
Algorithms & data structures easy

Stable merge two lists by custom comparator in Python

Merge two lists into one sorted output using a custom comparator while maintaining the original order of equal elements.

merge stable-sort custom-comparator
Python
from functools import cmp_to_key

def compare(x, y):
    # Custom comparator: sorts by length first, then by original index for stability
    if len(x) != len(y):
        return len(x) - len(y)
    return 0  # Equal keys preserve original order (stable)

def merge_stable(left, right, cmp_func):
    result = []
    i =…
13 0 Open

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