Optimal Head-Driven Parsing Complexity for Linear Context-Free Rewriting Systems

نویسندگان

  • Pierluigi Crescenzi
  • Daniel Gildea
  • Andrea Marino
  • Gianluca Rossi
  • Giorgio Satta
چکیده

We study the problem of finding the best headdriven parsing strategy for Linear ContextFree Rewriting System productions. A headdriven strategy must begin with a specified righthand-side nonterminal (the head) and add the remaining nonterminals one at a time in any order. We show that it is NP-hard to find the best head-driven strategy in terms of either the time or space complexity of parsing.

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تاریخ انتشار 2011