[gecode-users] Skipping branching alternatives?

[Guido Tack]

> I do not know whether BAB will be good enough as I do not know what Martin
> exactly needs. However I would also supsect that it will be BAB + X, where
> X might be to get more information from search so far.

I thought about that a bit yesterday, and BAB seems to be not enough. The 
problem is that you cannot express the pruning as a single constraint. E.g., 
if you find some solution with x=4 and want to prune all branches one level 
above that solution that have x!=4. Then you cannot simply say that x!=4 for 
all nodes explored later.
From what I understood, you need to limit the pruning to one particular choice 
point, and I cannot see how to achieve that using BAB. Or, in Luis' terms, 
the property Martin wants to express seems to be not global enough for BAB, 
but not local enough to be addressed by branchings and/or propagators alone. 
That's why you need a new search engine.

Cheers,
	Guido

-- 
Guido Tack
Programming Systems Lab, Saarland University, Germany
http://www.ps.uni-sb.de/~tack