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AIMA-Java Core Algorithms from the book Artificial Intelligence a Modern Approach 3rd Ed.

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package aima.core.search.informed;

import aima.core.search.framework.evalfunc.HeuristicFunction;
import aima.core.search.framework.qsearch.QueueSearch;

/**
 * Artificial Intelligence A Modern Approach (3rd Edition): page 93.

 * 

 * The most widely known form of best-first search is called A* Search
 * (pronounced "A-star search"). It evaluates nodes by combining g(n), the cost
 * to reach the node, and h(n), the cost to get from the node to the goal:

 * f(n) = g(n) + h(n).

 * 

 * Since g(n) gives the path cost from the start node to node n, and h(n) is the
 * estimated cost of the cheapest path from n to the goal, we have

 * f(n) = estimated cost of the cheapest solution through n.
 * 
 * @author Ravi Mohan
 * @author Mike Stampone
 * @author Ruediger Lunde
 */
public class AStarSearch extends BestFirstSearch {

	/**
	 * Constructs an A* search from a specified search space exploration
	 * strategy and a heuristic function.
	 * 
	 * @param impl
	 *            a search space exploration strategy (e.g. TreeSearch, GraphSearch).
	 * @param hf
	 *            a heuristic function h(n), which estimates the cost
	 *            of the cheapest path from the state at node n to a
	 *            goal state.
	 */
	public AStarSearch(QueueSearch impl, HeuristicFunction hf) {
		super(impl, new AStarEvaluationFunction(hf));
	}
}