A* search

In computer science, A* (pronounced “A star”) is a graph/tree search algorithm that finds a path from a given initial node to a given goal node (or one passing a given goal test). It employs a “heuristic estimate” that ranks each node by an estimate of the best route that goes through that node. It visits the nodes in order of this heuristic estimate. The A* algorithm is therefore an example of best-first search.
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<algorithm> A graph search algorithm. A* is guaranteed to find a minimal solution path before any other solution paths, if a solution exists, in other words, it is an "admissible" search algorithm. Each path is assigned a value based on the cost of the path (e.g. its length) and an (under)estimate of the cost of completing the path, i.e. the cost of a path from the end of the current path to a solution.
(1995-03-31)