Matrix
Matrix Cheat Sheet
A matrix is essentially a 2-dimensional array, and it's a common topic in coding interviews, especially in problems related to dynamic programming or graph traversal. While matrices can represent graphs, this guide focuses on non-graph matrix problems.
Corner Cases
Empty matrix: Ensure no arrays have zero length.
1 x 1 matrix: A matrix with a single element.
Matrices with only one row or column.
Recommended Practice Questions
After mastering the basics, try these:
Set Matrix Zeroes
Spiral Matrix
Rotate Image
Valid Sudoku
Additional Information
When dealing with matrix problems, it's important to be comfortable with various operations such as traversal, modification, and condition checking. Understanding how to efficiently create, copy, and transpose matrices can be particularly useful in solving a wide range of problems. Additionally, being able to handle corner cases effectively will ensure that your solutions are robust and can handle a variety of inputs during interviews.
Techniques for Working with Matrices
Creating an Empty Matrix
Often needed for traversal or dynamic programming problems to track states or store results.
Transposing a Matrix
Switching rows and columns can simplify the verification of conditions in grid-based games.
Practice Problems
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