public void Achievable()
{
var src = new Puzzle(new int[, ] {
{ 1, 2, 3 }, { 4, 5, 0 }
});
var dst = src.MoveSelf(Direction.Left).MoveSelf(Direction.Left).MoveSelf(Direction.Up);
Assert.IsTrue(PuzzleUtility.Reachable(src, dst));
Assert.IsFalse(PuzzleUtility.Reachable(src, new Puzzle(new int[, ] {
{ 1, 2, 3 }, { 5, 4, 0 }
})));
}
public static void Main()
{
//Read from console
int rowCount = ReadInteger("Row count: ");
int colCount = ReadInteger("Column count: ");
Puzzle src = ReadPuzzle(rowCount, colCount, "Source puzzle:\n");
Puzzle dst = ReadPuzzle(rowCount, colCount, "Destination puzzle:\n");
//Check reachability before searching
bool?reachable;
try {
reachable = PuzzleUtility.Reachable(src, dst);
}
catch (Exception ex) {
Console.WriteLine(ex.Message);
return;
}
if (reachable == false)
{
Console.WriteLine("Not reachable");
return;
}
//Read the heuristic function to be used. Function name must be presented in Evaluator class
string funcName;
do
{
Console.Write("Heuristic function: ");
funcName = Console.ReadLine();
}while (typeof(Evaluator).GetField(funcName) == null);
Search <Puzzle> .Evaluator estimate = (dynamic)(typeof(Evaluator).GetField(funcName).GetValue(null));
//Start searching
var search = new Search <Puzzle>(src, dst, PuzzleUtility.Transform);
var cost = search.AStar(estimate);
if (!cost.HasValue)
{
Console.WriteLine("Not reachable");
return;
}
Console.WriteLine($"Number of steps: {cost}");
//Render the search tree to an image
var graph = search.SearchSource.BuildSearchTree(out var indexToNode);
var stateToIndex = new Dictionary <Puzzle, int>();
for (int i = 0; i < indexToNode.Length; ++i)
{
stateToIndex.Add(indexToNode[i].State, i);
}
graph.SetNodeAttribute(attr => {
attr.Padding = 0.1;
attr.Color = Color.Black;
});
graph.FindNode(stateToIndex[search.Source].ToString()).Attr.Color = Color.Red;
graph.FindNode(stateToIndex[search.Destination].ToString()).Attr.Color = Color.Yellow;
graph.PaintPath(search.Path.Select(puzzle => stateToIndex[puzzle].ToString()), Color.Cyan);
string fileName = "search states.jpg";
graph.RenderImage(fileName, height: search.SearchSource.Height * 40 * (rowCount + 2));
Process.Start(new ProcessStartInfo()
{
FileName = fileName,
UseShellExecute = true
});
}
public void CountReversePairs()
{
Assert.AreEqual(0, PuzzleUtility.CountReversePairs(new int[] { 1, 2, 3, 4, 5 }));
Assert.AreEqual(10, PuzzleUtility.CountReversePairs(new int[] { 5, 4, 3, 2, 1 }));
Assert.AreEqual(13, PuzzleUtility.CountReversePairs(new int[] { 1, 9, 2, 6, 0, 8, 1, 7 }));
}
