Practice Arena

Python Coding
Challenges

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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

Python Basics easy

Compound interest

Return the future balance after compound interest, rounded to two decimals.

math functions finance

Python Basics easy

Grade from Score

Write a function that maps a numeric score to its letter grade using standard grading thresholds.

conditionals functions integers

Python Basics easy

Grade Calculator

Implement a function that converts a numeric score to a letter grade using a standard scale.

conditionals functions basic-syntax

Python Basics easy

Map, Filter, Reduce

Implement three functions using map, filter, and reduce to manipulate a list of integers.

map filter reduce

Python Basics easy

Variadic Sum Function

Implement a variadic function that sums an arbitrary number of numeric arguments.

functions args sum

Functions & Closures easy

Bind First Argument

Implement bind_first_arg, a decorator that fixes the first argument of any function.

decorators closures functions

OOP & Classes medium

Reentrant Lock Manager

Implement a ReentrantLock class with acquire, release, locked, owner, and helper functions that test thread-safety with real threads.

threading locking reentrant

Data Structures & Algorithms hard

LRU cache decorator

Implement @lru_cache(maxsize=N) for unary functions using OrderedDict.

decorators caching OrderedDict

Decorators & Context Managers easy

Once Decorator: Run a Function Only Once

Implement a decorator that caches and returns the result of the first call for subsequent calls.

decorators closures caching

Decorators & Context Managers easy

Print Args Decorator

Write a decorator that prints function name and arguments, then returns the original result.

decorators functions wrappers

Bit Manipulation medium

Bit Mask Permissions

Implement helper functions to compose bit masks and check permission bits using bitwise operators.

bitwise bitmasks permissions

Showing 11 challenges

Guide: free Python coding challenges

Practice Python by solving problems

PythonSkillset challenges are hands-on coding exercises from beginner to advanced. Open a challenge, read the problem, write Python in the split-pane editor, and run tests with Pyodide — no install required.

How to use the arena

Pick a category — basics, algorithms, strings, and more
Open a challenge, read the statement, and edit the starter code
Run tests, fix failures, then try a related quiz or tutorial lesson

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.