Python Coding Challenges

iterator generator flatten

Flatten Nested List Iterator

Implement a class that iterates over all integers in a nested list structure in depth-first order.

iterator-protocol class lazy-evaluation

Iterator protocol class

Implement a class that follows the iterator protocol and yields squared numbers up to a given limit.

generators iterators chunking

Batch Iterator

Implement a generator that yields batches of a given size from any iterable, including the final partial batch.

Zip Longest Fill

Create an iterator that yields lists from multiple iterables, padding with a fill value when lengths differ.

generators zip iteration

Graph DFS Generator

Implement a generator function that performs a depth-first traversal of a graph without recursion.

generators dfs graph

generators context-manager close-method

Close generator early

Wrap any iterable in a generator that tracks yielded items and supports close() correctly.

decorators closures caching

Once Decorator: Run a Function Only Once

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

decorators time performance

Timing Decorator

Implement a decorator that prints the execution time of a function.

context-manager classes timing

Context Manager Class

Implement a context manager class that measures execution time and sets duration, with None if an exception occurred.

decorators functions wrappers

Print Args Decorator

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

context-manager file-io python

File Open Context Manager

Create a class that acts as a context manager for opening a virtual file in memory.

context-manager timing measurement

Timer Context Manager

Implement a context manager that measures execution time of a with block and stores it.

context-managers stderr redirect

Suppress stderr manager

Implement a context manager that suppresses all output written to stderr during its block.

decorator context-manager time

Context Decorator Dual

Implement a timing decorator and a context manager that both record elapsed time in seconds.

decorator closure function

Count calls decorator

Implement a decorator that counts and reports how many times the wrapped function is called.

decorators logging function-wrappers

Log Calls Decorator

Create a decorator that prints call details and returns the original result.

context-manager threading lock

Lock Context Manager

Implement a Lock class with acquire/release and context manager support.

decorators class validation

Class-based decorator with call validation

Build a class-based decorator that validates a single argument's type and logs successful invocation.

+8 pts 15m

exceptions parsing default-value

Safe Integer from String

Implement safe_int that converts a string to an integer, returning a default value on any failure, with support for an optional base.

try-except division error-handling

Safe divide function

Implement safe_divide that returns None on ZeroDivisionError and TypeError.

exceptions parsing validation

Safe int parser

Implement safe_parse_int that converts a string to an int, returning a default value on failure.

Safe Float Parser

Write a function that safely converts a string to a float, returning None for invalid inputs.

float exception parsing

exceptions division error-handling

Divide with zero check

Write a function that safely divides two numbers, catching division by zero.

Key error handler

Implement a safe dictionary access function that returns a default value on missing keys.

exceptions dict fallback