Slides.
Slides.
Slides.
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
STEPHAN KREUTZER COMPLEXITY OF MODEL-CHECKING PROBLEMS 61/81<br />
INTRODUCTION COMPLEXITY UPPER BOUNDS COMPOSITION LOCALITY LOCALISATION GRIDS GRID-LIKE MINORS LABELLED WEBS<br />
Intractability on Grids<br />
Theorem. Let G be the class of coloured grids. Then MC(MSO,G) is not<br />
fixed-parameter tractable unless P=NP.<br />
Proof. Let SAT be the NP-complete propositional satisfiability problem.<br />
SAT can be solved in quadratic time by an NTM M.<br />
Given: SAT-instance w := (X 1 ∨¬X 3 ...) ˆ= 010...<br />
Look at the time-space diagram of an acc. run of M on w.
Change language