1. Introduction

Abstract

Constraint programming is an emergent software technology for declarative description and effective solving of large, particularly combinatorial, problems especially in areas of planning and scheduling. It has recently emerged as a research area that combines researchers from a number of fields, including Artificial Intelligence, Programming Languages, Symbolic Computing and Computational Logic. Constraint networks and constraint satisfaction problems have been studied in Artificial Intelligence starting from the seventies. Systematic use of constraints in programming has started in the eighties. In constraint programming the programming process consists of the generation of requirements (constraints) and solution of these requirements, by specialized constraint solvers.