C# – Convert an array to a list

The simplest way to convert an array to a list is with the ToList() Linq method: This outputs the following: Besides using ToList(), you can also use the list constructor or AddRange(). Before I show those, I’ll explain why you’d want to use these special methods instead of just adding items individually to a new … Read more

Comparing performance with Benchmark.NET graphs

The following graph compares the execution time of three sort implementations ran against varying input sizes (1k, 10k, 100k): This graph was generated using Benchmark.NET, which I’ll show how to use in this article. I’ll be comparing the performance of multithreaded quicksort implementations (with the non-threaded Array.Sort() as a baseline). Create console app and reference … Read more

C# – Pad a 2D array on all sides

Padding a 2D array on all sides means adding new rows on the top and bottom, new columns on the left and right, and then copying the original elements to the center of the padded array. It looks like this: There are two approaches for copying the elements. You can either copy individual items in … Read more

Multithreaded quicksort in C#

One day I decided to challenge myself by trying to implement multithreaded quicksort. I wanted to see how it would compare to the built-in Array.Sort() method. I came up with two algorithms that were 2-4x faster than Array.Sort(): After continuing to tinker, in attempts to further optimize, I came across the AsParallel().OrderBy() method (PLINQ). After … Read more