QCSP on partially reflexive forests

Barnaby Martin

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arXiv · 1103.6212

QCSP on partially reflexive forests

Barnaby Martin

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Abstract

We study the (non-uniform) quantified constraint satisfaction problem QCSP(H) as H ranges over partially reflexive forests. We obtain a complexity-theoretic dichotomy: QCSP(H) is either in NL or is NP-hard. The separating condition is related firstly to connectivity, and thereafter to accessibility from all vertices of H to connected reflexive subgraphs. In the case of partially reflexive paths, we give a refinement of our dichotomy: QCSP(H) is either in NL or is Pspace-complete.

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Barnaby Martin. 2011-03-31. QCSP on partially reflexive forests. https://arxiv.org/abs/1103.6212

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