public void BFSWithoutOrderByTest()
{
var queryable = HeuristicSearch.BestFirstSearch(start, goal, (step, lv) => step.GetFourDirections(unit));
var obstacles = new[] { new Point(5, 5), new Point(6, 6), new Point(7, 7), new Point(8, 8), new Point(9, 9) };
var solution = from step in queryable
from obstacle in obstacles
where step != obstacle
select step;
var exception = Assert.Throws <InvalidOperationException>(() => solution.ToList());
Assert.StartsWith("Unable to evaluate steps.", exception.Message);
}
public IEnumerator <object[]> GetEnumerator()
{
foreach (var setting in MapData.GetStartGoalCombinations())
{
var start = setting.Start;
var goal = setting.Goal;
var queryable = HeuristicSearch.BestFirstSearch(start, goal, (step, lv) => step.GetFourDirections(MapData.Unit));
var solution = from step in queryable.Except(MapData.Obstacles)
where step.X >= 0 && step.Y >= 0 && step.X <= 40 && step.Y <= 40
orderby step.GetManhattanDistance(goal)
select step;
yield return(new object[] { start, goal, solution.ToArray() });
}
}
public BestFirstSearchValidityTest()
{
var mapData = TestHelper.LoadMapData();
_start = mapData.Start;
_goal = mapData.Goal;
_obstacles = mapData.Obstacles;
_unit = 1f;
var queryable = HeuristicSearch.BestFirstSearch(_start, _goal, (step, lv) => step.GetFourDirections(_unit));
var solution = from step in queryable.Except(mapData.Obstacles)
where step.X >= 0 && step.Y >= 0 && step.X <= 40 && step.Y <= 40
orderby step.GetManhattanDistance(_goal)
select step;
_path = solution.ToList();
}
static void Main(string[] args)
{
while (true)
{
// http://www.8puzzle.com/images/8_puzzle_start_state_a.png
var initial = new BoardState(new[]
{
new Point(1, 2), // empty square
new Point(0, 1), // square 1
new Point(0, 0), // square 2
new Point(2, 0), // square 3
new Point(2, 1), // square 4
new Point(2, 2), // square 5
new Point(1, 1), // square 6
new Point(0, 2), // square 7
new Point(1, 0), // square 8
});
// http://www.8puzzle.com/images/8_puzzle_goal_state_a.png
var goal = new BoardState(new[]
{
new Point(1, 1), // empty square
new Point(0, 0), // square 1
new Point(1, 0), // square 2
new Point(2, 0), // square 3
new Point(2, 1), // square 4
new Point(2, 2), // square 5
new Point(1, 2), // square 6
new Point(0, 2), // square 7
new Point(0, 1), // square 8
});
Console.WriteLine("A)* Search");
Console.WriteLine("B)est-first Search");
Console.WriteLine("I)terative Deepening AStar Search");
Console.WriteLine("R)ecursive Best-first Search");
Console.Write("Select an algorithm: ");
var queryable = default(HeuristicSearchBase <BoardState, BoardState>);
// Initialize the algorithm with the callback that gets all valid moves.
switch (Console.ReadKey().Key)
{
case ConsoleKey.A:
queryable = HeuristicSearch.AStar(initial, goal, (board, lv) => board.GetNextSteps());
break;
case ConsoleKey.B:
queryable = HeuristicSearch.BestFirstSearch(initial, goal, (board, lv) => board.GetNextSteps());
break;
case ConsoleKey.I:
queryable = HeuristicSearch.IterativeDeepeningAStar(initial, goal, (board, lv) => board.GetNextSteps());
break;
case ConsoleKey.R:
queryable = HeuristicSearch.RecursiveBestFirstSearch(initial, goal, (board, lv) => board.GetNextSteps());
break;
default: continue;
}
Console.WriteLine();
// GetSumOfDistances() calculates the sum of Manhattan distance
// between each of square and its goal.
// -------------------------------------------------
var solution = from board in queryable
orderby board.GetSumOfDistances(goal)
select board;
// -------------------------------------------------
// Print out the solution.
foreach (var board in solution)
{
Console.WriteLine(board);
}
}
}
static void Main(string[] args)
{
var boundary = new Rectangle(0, 0, MapWidth, MapWidth);
var presentation = new char[MapHeight][];
while (true)
{
var queryable = default(HeuristicSearchBase <Point, Point>);
var solution = default(HeuristicSearchBase <Point, Point>);
var counter = 0;
var mapData = LoadMapData();
for (var y = 0; y < MapHeight; y++)
{
if (presentation[y] == null)
{
presentation[y] = new char[MapWidth];
}
for (var x = 0; x < MapWidth; x++)
{
var point = new Point(x, y);
if (mapData.Obstacles.Contains(point))
{
presentation[y][x] = ObstacleSymbol;
}
else if (point == mapData.Start)
{
presentation[y][x] = StartSymbol;
}
else if (point.Equals(mapData.Goal))
{
presentation[y][x] = GoalSymbol;
}
else
{
presentation[y][x] = SpaceSymbol;
}
}
}
Console.WriteLine("A)* Search");
Console.WriteLine("B)est-first Search");
Console.WriteLine("R)ecursive Best-first Search");
Console.WriteLine("I)terative Deepening AStar Search");
Console.Write("Select an algorithm: ");
// Initial the algorithm.
switch (Console.ReadKey().Key)
{
case ConsoleKey.A:
queryable = HeuristicSearch.AStar(mapData.Start, mapData.Goal, GetNextSteps);
break;
case ConsoleKey.B:
queryable = HeuristicSearch.BestFirstSearch(mapData.Start, mapData.Goal, GetNextSteps);
break;
case ConsoleKey.I:
queryable = HeuristicSearch.IterativeDeepeningAStar(mapData.Start, mapData.Goal, GetNextSteps);
break;
case ConsoleKey.R:
queryable = HeuristicSearch.RecursiveBestFirstSearch(mapData.Start, mapData.Goal, GetNextSteps);
break;
default: continue;
}
Console.WriteLine();
Console.WriteLine("C)hebyshev Distance Comparer");
Console.WriteLine("E)uclidean Distance Comparer");
Console.WriteLine("M)anhattan Distance Comparer");
Console.Write("Select comparer: ");
// Compare two positions and the goal position with selected distance.
switch (Console.ReadKey().Key)
{
case ConsoleKey.C:
solution = from step in queryable.Except(mapData.Obstacles)
where boundary.Contains(step)
orderby step.GetChebyshevDistance(mapData.Goal)
select step;
break;
case ConsoleKey.E:
solution = from step in queryable.Except(mapData.Obstacles)
where boundary.Contains(step)
orderby step.GetEuclideanDistance(mapData.Goal)
select step;
break;
case ConsoleKey.M:
solution = from step in queryable.Except(mapData.Obstacles)
where boundary.Contains(step)
orderby step.GetManhattanDistance(mapData.Goal)
select step;
break;
default: continue;
}
Console.WriteLine();
foreach (var step in solution)
{
if (step != mapData.Start && step != mapData.Goal)
{
presentation[(int)step.Y][(int)step.X] = PathSymbol;
}
counter++;
}
Array.ForEach(presentation, row => Console.WriteLine(string.Join(" ", row)));
Console.WriteLine("Total steps: {0}", counter);
}
}