Basic Calculator
Implement a function that evaluates a simple arithmetic expression with +, -, *, / and parentheses.
Find all numbers in text
Write a function that extracts all standalone integers from a text string using regular expressions.
Basic Calculator III
Implement a recursive descent parser to evaluate a fully parenthesized arithmetic expression with +, -, *, / and parentheses.
Basic Calculator II
Evaluate a basic arithmetic expression with +, -, *, / following operator precedence.
Validate phone number
Write a function that uses regular expressions to determine if a given string is a valid US phone number.
Match IPv4 Address
Write a function that uses a regular expression to check if a string is a valid IPv4 address.
Validate Hex Color Code
Write a function that validates hex color codes using regular expressions.
Match Balanced Parentheses with Regex
Write a function that uses regular expressions to determine if parentheses are balanced and properly nested.
Evaluate Reverse Polish Notation
Evaluate an arithmetic expression written in reverse Polish notation using a stack.
Showing 1–9 of 9 challenges
Guide: free Python coding challenges
Practice Python by solving problems
PythonSkillset challenges are hands-on coding exercises from beginner to advanced. Open a challenge, read the problem, write Python in the split-pane editor, and run tests with Pyodide — no install required.
How to use the arena
- Pick a category — basics, algorithms, strings, and more
- Open a challenge, read the statement, and edit the starter code
- Run tests, fix failures, then try a related quiz or tutorial lesson
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.