# Nonconstructive tools for proving polynomial-time decidability

@article{Fellows1988NonconstructiveTF, title={Nonconstructive tools for proving polynomial-time decidability}, author={M. Fellows and M. Langston}, journal={J. ACM}, year={1988}, volume={35}, pages={727-739} }

Recent advances in graph theory and graph algorithms dramatically alter the traditional view of concrete complexity theory, in which a decision problem is generally shown to be in P by producing an efficient algorithm to solve an optimization version of the problem. Nonconstructive tools are now available for classifying problems as decidable in polynomial time by guaranteeing only the existence of polynomial-time decision algorithms. In this paper these new methods are employed to prove… Expand

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