XCSP³ Specifications

XCSP³

XCSP³ is an XML-based format designed to represent combinatorial constrained problems. XCSP³

• is compact, easy to read and to parse,
• captures the structure of the problem models,
• introduces a limited set of basic constraint forms, and allows many variations of them,
• supports many frameworks introduced in the litterature: CSP, COP, WCSP, QCSP, DisCSP, SCSP, ...

See full specifications.

XCSP³-core

This is a subset of XCSP³, composed of the main concepts of Constraint Programming (although, of course, this is quite subjective). The interest of XCSP³-core is multiple:

• focusing on the most popular constraints,
• facilitating parsing through dedicated parsers in Java and C++,
• defining a core format for future competitions of constraint solvers.

See core specifications

XCSP³-core, targeted for CSP (Constraint Satisfaction Problem) and COP (Constrained Optimization problem), handles integer variables, mono-objective optimization, and 20 important constraints:

Importantly, as for full XCSP³, the structure of problems (models) can be preserved in XCSP³-core thanks to the following mechanisms:

• arrays of variables
• groups of constraints
• blocks of constraints
• annotations to express search and filtering advices