http://www.algorithmist.com/index.php/Merge_sort.c
See also:
http://stackoverflow.com/questions/159590/way-to-go-from-recursion-to-iteration
http://stackoverflow.com/questions/1557894/non-recursive-merge-sort
Info and improvements about actual sort used in Java collections:
https://arxiv.org/pdf/1412.0193.pdf
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhAwRu0AgrwxLE6S6nNBC1TiRJ5nc-W6cnpcVUDcZAIE8cj74Sb4mOkdlAYYd00XFLbNCnngYy-giFH34FmcXoZ_tn1wGdnKLy2_jLeAyDbcSEJXKFgGVyh52jaUXe9SPTdTFvwIurgzXc/s1600/Untitled.png)