Spiral Matrix Order
Given a 2D matrix, return all elements in clockwise spiral order starting from the top-left.
Number of Islands
Given a 2D grid of '1' (land) and '0' (water), count the number of islands surrounded by water.
Max Area of Island
Given a 2D grid of 0s and 1s, find the maximum area of a connected group of 1s.
Spiral Matrix Traversal
Implement a function that returns the elements of a 2D matrix in clockwise spiral order.
Search a 2D Matrix II
Implement an efficient search for a target in a matrix where each row and each column is sorted in ascending order.
Number of Islands in a Matrix
Count the number of distinct islands (connected groups of 1s) in a 2D binary matrix.
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.
Shift 2D Grid
Implement a function to shift a 2D grid right by k positions, flattening the grid and wrapping elements.
Matrix Block Sum
Given a 2D matrix and a block size, compute the sum of each block centered at every cell.
Transpose Matrix In-Place
Implement a function that transposes a square matrix in-place and returns the transposed matrix.
Word Search Matrix
Given a 2D board and a word, determine if the word can be formed by sequentially adjacent cells (horizontally or vertically), without reusing cells.
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.
Showing 13 challenges · Matrix & 2D Arrays
Matrix & 2D Arrays — Python coding challenges
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