Efficient context-free grammar constraints
Serdar Kadıoğlu, Meinolf Sellmann · 2008
With the introduction of constraints based on finite automata a new line of research has opened where constraints are based on formal languages. Recently, constraints based on grammars higher up in the Chomsky hierarchy were intro-duced. We devise a time- and space-efficient incremental arc-consistency algorithm for context-free grammars. Partic-ularly, we show how to filter a sequence of monotonically tightening problems in cubic time and quadratic space. Ex-periments on a scheduling problem show orders of magnitude improvements in time and space consumption.