On 4/9/22 13:45, Douglas McIlroy wrote:
Single Level
Storage is an awesome concept and removes so many ugly
hacks from algorithms that otherwise have to process data in files.
This was Vic Vyssotsky's signature contribution to Multics, though in typical
Vyssotsky fashion he never sought personal credit for it. Other awesome
Vyssotsky inventions:
[..]
A minimum-spanning-tree algorithm quite different from the well-known methods
due to his colleagues Bob Prim and Joe Kruskal, again unpublished.
Interesting, I had not heard about this before, and an internet search
turned up:
(some copy of "Algorithms in C++", by Robert Sedgewick)
https://apprize.best/science/algorithms_2/3.html
paragraph 4.3.23: graphs(4) -> mst(3) -> vyssotsky(23)
https://github.com/reneargento/algorithms-sedgewick-wayne/blob/master/src/c…
(an implementation of this by Rene Argento?)
Algorithms in Java, 3rd edition (2003) R. Sedgewick
20.72: Exercises:
[V. Vyssotsky] Develop an implementation of the algorithm discussed in
Section 20.2 that builds the MST by adding edges one at a time and
deleting the longest edges on the cycle formed (see Exercise 20.34). Use
a parent-link representation of a forest of MST subtrees. Hint: Reverse
links when traversing paths in trees.
I was unable to fetch this slide deck
https://web.archive.org/web/20081205054614/https://www.cs.princeton.edu/~rs…
which also appears to mention it at least in passing: "Other MST
algorithms VYSSOTSKY (1960s) add edges one at a time delete longest on
cycle formed"
Does anyone know of a more complete source on this topic?
It is not mentioned on Wikipedia, these seem like appropriate places to
place a reference:
https://en.wikipedia.org/wiki/Minimum_spanning_tree
https://en.wikipedia.org/wiki/Victor_A._Vyssotsky