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.
01 Matrix Nearest Zero
Given a binary matrix, return a matrix of the same shape where each cell contains the Manhattan distance to the nearest 0.
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.
Shortest Path in Binary Matrix
Compute the shortest path length from top-left to bottom-right in a binary matrix using 8-directional moves.
Count square submatrices with all ones
Count all square submatrices consisting entirely of 1s in a binary matrix.
Largest Plus Sign
Compute the largest possible plus sign of 1s in an n x n grid with some cells set to 0.
Matrix Block Sum
Given a 2D matrix and a block size, compute the sum of each block centered at every cell.
Rotate Matrix Layers
Given a square matrix, rotate each concentric layer 90 degrees clockwise.
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.
Pacific Atlantic Flow
Given a height matrix, return all cells from which water can flow to both the Pacific and Atlantic oceans.
Pacific Atlantic Matrix DFS
Given a matrix of heights, return cells that can reach both Pacific and Atlantic oceans using a DFS approach.
Showing 1–15 of 15 challenges · medium · Matrix & 2D Arrays
Matrix & 2D Arrays — Python coding challenges
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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.
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