how many variations of merge sort there are?

Question

i'm looking to find how many different implementation of merge sort in .net there are because i was checking this post Sorting Algorithms in VB.Net: How To Implement Merge Sort and the article mentions that there are several other versions such as in-place and dunno what else...

Answer 1

Too many to count. As you can see here: http://en.wikipedia.org/wiki/Merge_sort, there are optimizations depending on the CPU for example. You can also always choose a different .NET language (a functional language like F# might be interesting) and you can also create a multi-threaded version. For in-place sorting: If you can create a sorting algorithm that works in-place, it only needs O(n) space and not (for example) O(n log n). This might be important for large datasets.

I guess there's been a lot of research on Merge Sort, so just check the papers on that topic if you need more implementations/variations.