<complexity> A normal (deterministic) Turing Machine that has a "guessing head" - a write-only head that writes a guess at a solution on the tape first, based on some arbitrary internal algorithm. The regular Turing Machine then runs and returns "yes" or "no" to indicate whether the solution is correct.
A nondeterministic Turing Machine can solve nondeterministic polynomial time computational decision problems in a number of steps that is a polynomial function of the size of the input
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Nearby terms: nondeterministic « nondeterministic automaton « nondeterministic polynomial time « Nondeterministic Turing Machine » non-impact printer » non-interlaced » nonintrusive testing