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467 challenges 330 easy 120 medium 17 hard

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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

Interleave Two Strings

Given two strings s1 and s2, return a new string that interleaves them character by character, starting with s1.

strings merging loops

Strings & Text easy

Find substring index

Implement a function that returns the starting index of the first occurrence of a substring using only basic string indexing and slicing.

string search index

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.