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925 challenges 556 easy 323 medium 46 hard

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Recursion & Backtracking easy

Wildcard Match (Simple)

Write a function that checks whether a string matches a pattern with '*' and '?' wildcards.

wildcard recursion string

Recursion & Backtracking medium

Generate Parentheses

Given n, generate all valid strings of n pairs of parentheses.

backtracking recursion parentheses

Recursion & Backtracking medium

Letter Combinations of a Phone Number

Given a string of digits, return all possible letter combinations that the number could represent on a phone keypad.

recursion backtracking string

Recursion & Backtracking medium

Word Search Backtrack

Determine if a given word exists in a 2D board by tracing adjacent cells without reusing any cell.

backtracking matrix dfs

Recursion & Backtracking medium

Palindrome Partitioning

Given a string s, return all possible palindrome partitioning of s.

backtracking recursion palindrome

Recursion & Backtracking hard

Remove invalid parentheses

Given a string with parentheses and letters, return all valid strings after removing the minimum number of invalid parentheses.

backtracking parentheses string

Recursion & Backtracking medium

Letter Tile Possibilities

Given a string of letter tiles, count the number of distinct non-empty sequences that can be formed using any non-empty subset in any order.

backtracking counting strings

Showing 1–7 of 7 challenges · Recursion & Backtracking

Recursion & Backtracking — Python coding challenges

What you will find here

This page lists recursion & backtracking 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.