C# – Convert list to array

The simplest way to convert a list to an array is to use the List.ToArray() method: This outputs the following: Internally, the List<T> class stores elements in a dynamically sized array (it resizes when necessary). So under the hood, List.ToArray() uses Array.Copy() to copy the list’s internal array to a new array. This is very … Read more

C# – Remove a list of characters from a string

When you want to remove a list of characters from a string, loop through the list and use string.Replace(): Note that string.Replace() returns a new string (because strings are immutable). Running this outputs the following: This is the fastest approach (in .NET 6+). Linq approach: Where() + ToArray() + new string() Another option for removing … 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