what kind of algorithm in this code?

[pogood20]

https://gist.github.com/douglas-vaz/5331386

i tried the code and it succeed, and now i want to know what algorithm is used in that code, like generate and test, best first search, hill climb or something like that

[JLBorges]

The code has this at the top:

/**
 * Based on the paper "A Heuristic for Solving the Generalized Water Jug Problem 
 * Florin Leon, Mihai Zaharia, Dan Galea
 */

A web search (Duck) lead to this:
https://www.researchgate.net/publication/264910907_A_heuristic_method_for_solving_the_generalized_water_jugs_problem
(There is a button to download the pdf on the top right of the page.)