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Python Coding
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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

Lists & Arrays medium

Maximum subarray (Kadane)

Find the contiguous subarray with the largest sum.

dp arrays kadane

Lists & Arrays hard

Sliding window maximum

Return the maximum of each window of size k as it slides across an array.

sliding-window deque arrays

Lists & Arrays easy

Running Maximum

Implement a function that returns a list where each element is the largest value seen so far.

lists cumulative maximum

Lists & Arrays medium

Partition Array

Implement a function that finds a contiguous partition of a list into k groups, minimizing the maximum sum of the groups.

arrays partition contiguous

Showing 4 challenges · Lists & Arrays

Lists & Arrays — Python coding challenges

What you will find here

This page lists lists & arrays 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.