Example #1
0
        public Tuple <List <object>, int> GetLongestPath(ISearchNode startState, ISearchNode goalState = null, bool verbose = false)
        {
            if (verbose)
            {
                Console.Clear();
            }
            Stopwatch searchWatch = new Stopwatch();

            searchWatch.Start();
            openQueue = new SimplePriorityQueue <ISearchNode>();
            closedSet = new HashSet <ISearchNode>();

            openQueue.Enqueue(startState, 0);
            long                   step = 0;
            ISearchNode            current;
            HashSet <ExpandAction> expandActions;
            ISearchNode            newNode;
            ISearchNode            match;
            var targetCandidates = new List <Tuple <List <object>, int> >();

            while (openQueue.Count > 0)
            {
                step++;
                current = openQueue.Dequeue();

                closedSet.Add(current);
                if (current.IsGoalState(goalState))
                {
                    //todo: this can probably be optimized to work more like standard A*, but negating Cost + Heuristic wasn't enough and this is probably the next best thing. Or at least it's the next thing I came up with.
                    targetCandidates.Add(Tuple.Create(current.Actions, current.Cost));
                    continue;
                }

                expandActions = current.ExpandNode();

                if (verbose)
                {
                    OutputVerboseInfo(goalState, searchWatch, step, current);
                }

                foreach (ExpandAction expandAction in expandActions)
                {
                    newNode      = expandAction.Result;
                    newNode.Cost = current.Cost + expandAction.Cost;
                    newNode.Actions.Add(expandAction.Action);
                    if (closedSet.Any(x => x.Equals(newNode)))
                    {
                        continue;
                    }
                    match = openQueue.SingleOrDefault(x => x.Equals(newNode));
                    if (match != default(ISearchNode))
                    {
                        if (match.Cost < newNode.Cost)
                        {
                            openQueue.UpdatePriority(match, -1 * (newNode.Cost + newNode.GetHeuristic(goalState)));
                        }
                    }
                    else
                    {
                        openQueue.Enqueue(newNode, -1 * (newNode.Cost + newNode.GetHeuristic(goalState)));
                    }
                }
            }

            return(targetCandidates.OrderByDescending(c => c.Item2).First());
        }
Example #2
0
        public Tuple <List <object>, int> GetOptimalPath(SearchNode startState, SearchNode goalState = null, bool verbose = false)
        {
            if (verbose)
            {
                Console.Clear();
            }
            Stopwatch searchWatch = new Stopwatch();

            searchWatch.Start();
            openQueueNew = new SimplePriorityQueue <SearchNode>();
            closedSetNew = new HashSet <SearchNode>();

            openQueueNew.Enqueue(startState, 0);
            long       step = 0;
            SearchNode current;
            HashSet <ExpandActionNew> expandActions;
            SearchNode newNode;
            SearchNode match;

            while (openQueueNew.Count > 0)
            {
                step++;
                current = openQueueNew.Dequeue();

                if (current.IsGoalState(current))
                {
                    return(Tuple.Create(current.Actions, current.Cost));
                }
                closedSetNew.Add(current);

                expandActions = current.ExpandNode();

                if (verbose)
                {
                    OutputVerboseInfo(goalState, searchWatch, step, current);
                }


                foreach (ExpandActionNew expandAction in expandActions)
                {
                    newNode      = expandAction.Result;
                    newNode.Cost = current.Cost + expandAction.Cost;
                    newNode.Actions.Add(expandAction.Action);
                    if (closedSetNew.Contains(newNode))
                    {
                        continue;
                    }
                    match = openQueueNew.SingleOrDefault(x => x.Equals(newNode));
                    if (match != null)
                    {
                        if (match.Cost > newNode.Cost)
                        {
                            openQueueNew.UpdatePriority(match, newNode.Cost + newNode.GetHeuristic(goalState));
                        }
                    }
                    else
                    {
                        openQueueNew.Enqueue(newNode, newNode.Cost + newNode.GetHeuristic(goalState));
                    }
                }
            }

            return(Tuple.Create(new List <object>(), -1));
        }
Example #3
0
        // ReSharper disable once MemberCanBePrivate.Global
        public Tuple <List <object>, int> GetOptimalPath(ISearchNode startState, ISearchNode goalState = null, bool verbose = false, bool stepByStep = false)
        {
            if (verbose)
            {
                Console.Clear();
            }
            Stopwatch searchWatch = new Stopwatch();

            searchWatch.Start();
            openQueue = new SimplePriorityQueue <ISearchNode>();
            closedSet = new HashSet <ISearchNode>();

            openQueue.Enqueue(startState, 0);
            long                   step = 0;
            ISearchNode            current;
            HashSet <ExpandAction> expandActions;
            ISearchNode            newNode;
            ISearchNode            match;

            while (openQueue.Count > 0)
            {
                step++;
                current = openQueue.Dequeue();

                if (current.IsGoalState(goalState))
                {
                    return(Tuple.Create(current.Actions, current.Cost));
                }
                expandActions = current.ExpandNode();
                closedSet.Add(current);

                if (verbose)
                {
                    OutputVerboseInfo(goalState, searchWatch, step, current);
                    if (stepByStep)
                    {
                        Console.ReadLine();
                    }
                }

                foreach (ExpandAction expandAction in expandActions)
                {
                    newNode      = expandAction.Result;
                    newNode.Cost = current.Cost + expandAction.Cost;
                    newNode.Actions.Add(expandAction.Action);
                    if (closedSet.Any(x => x.Equals(newNode)))
                    {
                        continue;
                    }
                    match = openQueue.SingleOrDefault(x => x.Equals(newNode));
                    if (match != default(ISearchNode))
                    {
                        if (match.Cost > newNode.Cost)
                        {
                            openQueue.UpdatePriority(match, newNode.Cost + newNode.GetHeuristic(goalState));
                        }
                    }
                    else
                    {
                        openQueue.Enqueue(newNode, newNode.Cost + newNode.GetHeuristic(goalState));
                    }
                }
                OnSearchNodeProcessed(new SearchEventArgs
                {
                    ClosedSet   = closedSet,
                    OpenQueue   = openQueue,
                    CurrentNode = current
                });
            }

            return(Tuple.Create(new List <object>(), -1));
        }