Multiplication Table Row
Return the nth row of a multiplication table as a list of 1..n products.
Product except self
Return an array where output[i] is the product of all elements except nums[i], without using division.
Running Product of Integers
Given a list of integers, return a new list where each element at index i is the product of all elements from index 0 to i.
Product of All Except Zeros Handling
Given a list of integers, return a list where each element is the product of all other elements, handling zeros correctly.
Cartesian Product Pairs
Create a function that returns the Cartesian product of two lists as a sorted list of lists.
Pivot sales by product
Write a function that pivots sales records into a dictionary keyed by product with monthly totals.
2D Vector dataclass
Implement a Vector2D dataclass with +, -, scalar *, dot product, and magnitude.
Cartesian Product Generator
Implement a generator function that yields the Cartesian product of multiple input iterables without precomputing all results.
Dot Product of Vectors
Implement a function that returns the dot product of two numeric vectors.
Kadane Variant: Maximum Product Subarray
Implement max_product_subarray(nums) that returns the maximum product of any contiguous subarray.
Integer Break Product
Given a positive integer n, break it into at least two positive integers that sum to n and maximize their product.
Subarray product less than K
Count contiguous subarrays where the product of all elements is strictly less than a target K.
Matrix Multiply 2D
Write a function that multiplies two 2D matrices (lists of lists) and returns the product matrix.
Cumulative Sum SQL
Write a SQL query to compute cumulative sales totals per product ordered by sale date.
Dot product of two vectors
Return sum of element-wise products.
Showing 1–15 of 15 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.