public static Node <State> Search(IProblem <State> problem, IFringe <Node <State> > fringe)
{
Func <Node <State>, Node <State>, int> compareStatesPriority = (node1, node2) =>
{
return(problem.CompareStatesPriority(node1.NodeState, node2.NodeState));
};
Func <Node <State>, Node <State>, int> compareStatesPriorityWithPathCost = (node1, node2) =>
{
return(problem.CompareStatesPriorityWithPathCost(node1.NodeState, node2.NodeState, node1.PathCost, node2.PathCost));
};
fringe.SetPriorityMethod(compareStatesPriority, compareStatesPriorityWithPathCost);
fringe.Add(new Node <State>(problem.InitialState, null, 0.0));
while (!fringe.IsEmpty)
{
var node = fringe.Pop();
if (problem.IsGoal(node.NodeState))
{
return(node);
}
foreach (var state in problem.Expand(node.NodeState))
{
if (!node.OnPathToRoot(state, problem.AreStatesTheSame))
{
var newNode = new Node <State>(state, node, node.PathCost + problem.CalculateCostToNextState(node.NodeState, state));
fringe.Add(newNode);
}
}
}
return(null);
}