Practice Arena

Python Coding
Challenges

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925 challenges 556 easy 323 medium 46 hard

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Stacks & Queues easy

Balanced brackets in string

Check if a string of brackets is properly balanced using a stack-based approach.

stack string parsing

Stacks & Queues medium

Evaluate Reverse Polish Notation

Evaluate an arithmetic expression written in reverse Polish notation using a stack.

stacks arithmetic parsing

Stacks & Queues medium

Decode String Stack

Decode a compressed string with repeated substrings like '3[a2[c]]' to 'accaccacc' using a stack-based approach.

stacks string parsing

Stacks & Queues medium

Score of Parentheses

Given a balanced parentheses string, compute its score where () is 1 and concatenation sums, nesting multiplies by 2.

stack string parsing

Stacks & Queues medium

Decode Nested String

Implement a function that decodes a string with nested encoding patterns.

stack string parsing

Showing 1–5 of 5 challenges · Stacks & Queues

Stacks & Queues — Python coding challenges

What you will find here

This page lists stacks & queues 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.