# IDP 3

## Team

- Bart Bogaerts (KU Leuven)
- Maurice Bruynooghe (KU Leuven)
- Broes De Cat (KU Leuven)
- Marc Denecker (KU Leuven)
- Jo Devriendt (KU Leuven)
- Joachim Jansen (KU Leuven)
- Pieter Van Hertum (KU Leuven)
- Stef De Pooter (KU Leuven)

## Description

IDP 3 uses FO(ID,Agg) + Lua as input language.

Model generation/optimization is achieved by lifted unit propagation + grounding with bounds (possibly using XSB for evaluating definitions) + applying the search algorithm MinisatID.

The integration with Lua (with logic components as first-class citizens) is used for pre- and postprocessing and to implement more complex inferences.

## System Settings

System versions:

- IDP 3.1.4
- MinisatID 3.7.4
- XSB 3.3

We will refer to the following options:

- cpsupport = using finite domain variables and constraints during search
- lazy grounding = interleaving grounding and search.
- xsb = evaluation of definitions with only 2-valued open symbols before search, by applying the XSB Prolog system.
- symmetrybreaking = automated symmetry detection + addition of static symmetry breaking formulas to the theory.
- groundwithbounds = derive bounds on necessary variable instantations during grounding. by reasoning based on the input interpretation + improve the order of instantiation.
- liftedunitpropagation = apply approximative unit propagation on the non-ground theory.

By default, the first 4 are disabled and the last 2 are enabled. Only options not taking their default value are mentioned.

**System Track**: lazy grounding, xsb, cpsupport.

- FO(.)^IDP is used as input language.

**Model-and-Solve Track**:

- N01 Permutation Pattern Matching: cpsupport, groundwithbounds off, liftedunitpropagation off
- N02 Valves Location Problem: symmetrybreaking, cpsupport
- N04 Connected Density Maximum Still life: symmetrybreaking, cpsupport, xsb
- N05 Graceful Graphs: cpsupport
- N06 Bottle Filling
- N07 Nomystery: symmetrybreaking
- N08 Sokoban: xsb, symmetrybreaking
- N09 Ricochet Robots
- N12 Strategic Companies
- O10 Crossing Minimization: xsb, cpsupport
- O11 Reachability: liftedunitpropagation off, lazy grounding
- O13 Solitaire: cpsupport
- O14 Weighted Sequence Problem: cpsupport, groundwithbounds off, liftedunitpropagation off
- O15 Stable Marriage: xsb, cpsupport
- O16 Incremental Scheduling: symmetrybreaking, xsb, cpsupport

## References

Participant URL.

Wittocx J., Marien M. and Denecker M.,

*The idp system: a model expansion system for an extension of classical logic*. LASH 2008.