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Python Coding Challenges

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925 challenges 556 easy 323 medium 46 hard
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

Disjoint Set Check

Check if two lists are disjoint by verifying they have no common elements.

sets list membership
+10 pts 15m
Dicts & Sets easy

Subset of another set

Write a function that checks if every element of one set is contained in another.

sets subset membership
+10 pts 10m
Dicts & Sets easy

Frequency sort descending

Write a function that sorts a list by frequency descending while preserving original order for ties.

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

Count Pairs with Sum

Implement a function that counts the number of distinct pairs in a list summing to a target.

dictionary pair-counting hash-map
+10 pts 15m
Dicts & Sets easy

Ransom Note Builder

Given two strings, determine if the ransom note can be formed from the words in the magazine.

dictionary counting strings
+10 pts 15m
Dicts & Sets easy

Longest Harmonious Subsequence

Given a list of integers, find the length of the longest harmonious subsequence where the difference between maximum and minimum values is exactly 1.

hash-map counting subsequence
+10 pts 15m
Dicts & Sets easy

Group by Department

Implement a function that groups a list of employee dictionaries by department, returning a dictionary keyed by department with lists of employee dictionaries.

dicts loops grouping
+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
Dicts & Sets easy

Pivot sales by product

Write a function that pivots sales records into a dictionary keyed by product with monthly totals.

dicts grouping aggregation
+10 pts 15m

Showing 25–34 of 34 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.