[gecode-users] Optimizing the constraint

[Jeffrey]

I'm optimizing my constraints with Gist at the moment.
I've found that there are lots of pruned tree on the left hand side.
These trees may span up to 4-5 levels.
Unfortunately, when I trigger gist to print out the dead node, I didn't find any values that is making any constraints failed. I had tried to add implied constraints which had already improve the speed for some cases. 


I'm currently using: INT_VAR_SIZE_MAX, INT_VAL_MIN   for branching an IntVarArray.
 
(1) What problems may it be? Is there any dynamic implied constraint in Gist?
(2) If I found that many dead node of a big pruned tree is found by the last assignment of values, How can I make such assignment comes earlier? e.g. Assign variables with more constraints first? Is it possible for Gist?
(3) Do you mind if I send up my little program for you to understand more about the Gist tree span?
(4) Although i use "INT_VAR_SIZE_MAX", it doesn't assign all values at once. Is that a bug or i'm misunderstanding its use? "INT_VAR_RND" is not suitable to me cause I want the search to be deterministic.
(5) Is there any other tricks I could use to sort out the problem? e.g. Deleting the constraint one by one to see which constraint is making it goes so long?
(6) Is there another symthoms i should try to look at the gist tree to get hint about the problem? e.g. what propagation setting should it be.

Big thanks again.


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