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Python Coding
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467 challenges 330 easy 120 medium 17 hard

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Strings & Text medium

Longest common prefix

Find the longest common prefix among a list of strings.

Strings & Text easy

Find all indexes of a substring

Write a function that returns a list of all starting indexes where a substring appears in a string, including overlapping occurrences.

substring string searching

Strings & Text easy

Safe Command Executor

Implement emulate_run that simulates running a command list and returns output and exit code.

string-parsing simulation lists

Showing 3 challenges · Strings & Text

Strings & Text — Python coding challenges

What you will find here

This page lists strings & text 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.