Valid Sudoku Board
Determine if a 9x9 Sudoku board is valid by checking rows, columns, and 3x3 sub-boxes.
Rotate Image 90 Degrees Clockwise
Rotate a square matrix 90 degrees clockwise and return the rotated matrix.
Valid Sudoku Validator
Determine if a given 9x9 Sudoku board is valid by checking rows, columns, and 3x3 boxes.
Toeplitz Matrix Check
Write a function is_toeplitz(matrix) that checks if a 2D list is a Toeplitz matrix, where all elements on the same diagonal from top-left to bottom-right are identical.
Diagonal Traverse Matrix
Implement a function that returns all elements of a matrix in diagonal zigzag order.
Transpose Matrix In-Place
Implement a function that transposes a square matrix in-place and returns the transposed matrix.
Matrix Multiply 2D
Write a function that multiplies two 2D matrices (lists of lists) and returns the product matrix.
Transpose 2D Array
Implement a function that returns the transpose of a rectangular 2D list.
Flipping an Image
Implement a function that flips an image represented as a binary matrix by reversing each row and inverting each pixel.
Showing 1–9 of 9 challenges · easy · Matrix & 2D Arrays
Matrix & 2D Arrays — Python coding challenges
What you will find here
This page lists matrix & 2d arrays 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.