@pardouin Thanks for the comment!
As for the tags, have a look at the first message in the contribution comments:
[CG]Thibaud > Updating the tag “Exhaustive Search” to “Brute Force” as it’s the only puzzle using the former.
I think “Exhaustive Search” was an acceptable tag for this puzzle, maybe “Brute Force” is not as appropriate indeed, but whatever… Anyway it’s a hard puzzle so one should expect to have to think about it twice before coding.