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Python Coding Challenges

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791 challenges 498 easy 262 medium 31 hard
Dicts & Sets easy

List intersection

Return the sorted list of elements common to both lists.

sets intersection
+8 pts 8m
Dicts & Sets easy

Keys Sorted by Value Descending

Given a dictionary mapping strings to integers, return a list of keys sorted by value descending, and when values tie, alphabetically ascending.

sorting dictionaries ordering
+8 pts 10m
Dicts & Sets easy

Anagram Dictionary Groups Lite

Group a list of words into anagrams using a dictionary keyed by sorted characters.

dicts strings anagrams
+10 pts 15m
Dicts & Sets easy

Common Keys of Two Dictionaries

Implement a function that finds keys shared by two dictionaries and returns them sorted.

dict set sorting
+8 pts 10m
Dicts & Sets easy

Union of Many Sets

Implement a function that takes any number of sets and returns a sorted list of their union.

sets union flatten
+10 pts 10m
Dicts & Sets easy

Anagram Groups by Size

Group a list of words into anagram groups and return them sorted by group size and lexicographically.

dicts sets sorting
+10 pts 10m
Dicts & Sets easy

Top K Frequent Words

Given a list of words, return the k most frequent words sorted by frequency (descending) and then alphabetically.

dictionary sorting frequency
+10 pts 15m
Dicts & Sets easy

Symmetric Difference

Write a function that computes the symmetric difference of two lists, returning a sorted list of unique elements.

sets set-operations symmetric-difference
+8 pts 10m
Dicts & Sets easy

Revenue by Month

Write a function that groups a list of (date, amount) pairs by year-month and returns total revenue per month as a sorted dictionary.

dict aggregation sales
+8 pts 10m

Showing 9 challenges · easy · Dicts & Sets

Dicts & Sets — Python coding challenges

What you will find here

This page lists dicts & sets challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.

Challenges vs tutorials and quizzes

Challenges test what you can build under constraints. For guided teaching, use our Python tutorials. For quick checks, try quizzes or copy snippets from code samples.