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NP-


NP-: /N-P/ pref. Extremely. Used to modify adjectives
   describing a level or quality of difficulty; the connotation is
   often `more so than it should be' (NP-complete problems all seem
   to be very hard, but so far no one has found a good a priori
   reason that they should be.)  "Coding a BitBlt implementation to
   perform correctly in every case is NP-annoying."  This is
   generalized from the computer-science terms `NP-hard' and
   `NP-complete'.  NP is the set of Nondeterministic-Polynomial
   algorithms, those that can be completed by a nondeterministic
   Turing machine in an amount of time that is a polynomial function
   of the size of the input; a solution for one NP-complete problem
   would solve all the others.  Note, however, that the NP- prefix is,
   from a complexity theorist's point of view, the wrong part of
   `NP-complete' to connote extreme difficulty; it is the completeness,
   not the NP-ness, that puts any problem it describes in the
   `hard' category.