best-first search

Best-first search is a search algorithm which optimizes breadth-first search by expanding the most promising node chosen according to some rule.Judea Pearl described best-first search as estimating the promise of node n by a "heuristic evaluation function which, in general, may depend on the description of n, the description of the goal, the information gathered by the search up to that point, and most important, on any extra knowledge about the problem domain." This general sense of the term is used by many authors, including Russell & Norvig.
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