Python Coding Challenges

Practice Python step by step. Code, run tests, and ask the AI Tutor for hints.

4 Challenges Available

All Challenges Basics Loops Strings Lists Dictionaries Functions Data Structures Algorithms OOP Biopython

Reverse a String

Write a function solution(s) that returns the string s reversed. Example solution("hello") → "oll...

strings Solve →

Count Vowels

Write a function solution(s) that returns the count of vowels (a, e, i, o, u — both upper and lower ...

strings Solve →

Check Palindrome

Write a function solution(s) that returns True if s is a palindrome (reads the same forwards and bac...

strings Solve →

Caesar Cipher

Write a function solution(text, shift) that encrypts text using a Caesar cipher with the given shift...

strings Solve →

Every challenge runs your code by calling a function. You must define a function named solution(...) that returns the answer.

Key rule: use return — not print(). The grader only checks the returned value; anything you print is ignored.

✗ Won't be graded

def solution(a, b):
    print(a + b)

✓ Correct

def solution(a, b):
    return a + b

What the grader sends

Your function is called with the challenge's test inputs, for example:

solution(3, 5)   # expects 8

Match the parameter names and count shown in the challenge description, and always finish with a return.