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467 challenges 330 easy 120 medium 17 hard

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All Python Basics Strings & Text Lists & Arrays Dicts & Sets Functions & Closures OOP & Classes Data Structures & Algorithms Advanced Python Iterators & Generators Decorators & Context Managers Error Handling & Exceptions Regular Expressions Math & Number Theory Bit Manipulation Dynamic Programming Trees & Binary Trees Graphs & Graph Algorithms Recursion & Backtracking Greedy Algorithms Binary Search Two Pointers & Sliding Window Stacks & Queues Heaps & Priority Queues Linked Lists Matrix & 2D Arrays Datetime & Time Calculations Data Formats & Parsing SQL & SQLite Numpy & Vectorized Computing Cryptography & Hashing

Dicts & Sets easy

Word to Index Map

Create a function that returns a dictionary mapping each unique word to the index of its first occurrence.

dictionary mapping indexing

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

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

Dicts & Sets easy

Mode of a list via counting

Implement a function that returns the mode of a list, resolving ties by the element that appears first.

counting dictionaries mode

Showing 4 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.