private static List <MazeCell> FindShortestPath(MazeCell entryCell, MazeCell exitCell, MazeCell currentCell, Queue <MazeCell> mazeQueue, MazeCell[,] mazeArray)
{
currentCell = entryCell;
mazeQueue.Enqueue(currentCell);
while (mazeQueue.Count > 0)
{
currentCell = MazeQueue.Dequeue();
mazeArray[currentCell.Y, currentCell.X].IsVisited = true;
if (currentCell == exitCell)
{
break;
}
if (mazeArray[currentCell.Y - 1, currentCell.X].IsVisited == false)
{
mazeArray[currentCell.Y - 1, currentCell.X].Parent = mazeArray[currentCell.Y, currentCell.X];
mazeQueue.Enqueue(mazeArray[currentCell.Y - 1, currentCell.X]);
}
if (mazeArray[currentCell.Y + 1, currentCell.X].IsVisited == false)
{
mazeArray[currentCell.Y + 1, currentCell.X].Parent = mazeArray[currentCell.Y, currentCell.X];
mazeQueue.Enqueue(mazeArray[currentCell.Y + 1, currentCell.X]);
}
if (mazeArray[currentCell.Y, currentCell.X - 1].IsVisited == false)
{
mazeArray[currentCell.Y, currentCell.X - 1].Parent = mazeArray[currentCell.Y, currentCell.X];
mazeQueue.Enqueue(mazeArray[currentCell.Y, currentCell.X - 1]);
}
if (mazeArray[currentCell.Y, currentCell.X + 1].IsVisited == false)
{
mazeArray[currentCell.Y, currentCell.X + 1].Parent = mazeArray[currentCell.Y, currentCell.X];
mazeQueue.Enqueue(mazeArray[currentCell.Y, currentCell.X + 1]);
}
}
var mazePath = new List <MazeCell>();
var start = mazeArray[entryCell.Y, entryCell.X];
var exit = mazeArray[exitCell.Y, exitCell.X];
mazePath.Add(exit);
while (exit != start)
{
if (exit.Parent == null)
{
return(null);
}
mazePath.Add(exit.Parent);
exit = exit.Parent;
}
mazePath.Reverse();
mazePath.RemoveAt(0);
return(mazePath);
}
public static void GetPathForVisualization(List <MazeCell> mazePath)
{
if (mazePath == null)
{
MazeArray[ExitCell.Y, ExitCell.X].Character = 'x';
MazeArray[ExitCell.Y, ExitCell.X].IsVisited = true;
MazeToBeShowed[ExitCell.Y - 1, ExitCell.X - 1] = new MazeCell(ExitCell.X - 1, ExitCell.Y - 1, MazeArray[ExitCell.Y, ExitCell.X].Character);
StoredMazeArray[ExitCell.Y, ExitCell.X] = MazeArray[ExitCell.Y, ExitCell.X];
CopyMaze(MazeArray, StoredMazeArray);
CopyMaze(StoredMazeToBeShowed, MazeToBeShowed);
MazeQueue.Clear();
}
else
{
foreach (var mazeCell in mazePath)
{
if (mazeCell.Character != ExitCell.Character)
{
MazeArray[mazeCell.Y, mazeCell.X].Character = '.';
}
else
{
MazeArray[mazeCell.Y, mazeCell.X].Character = '@';
ExitCell.Character = MazeArray[mazeCell.Y, mazeCell.X].Character;
}
}
var canvasPath = new List <MazeCell>();
foreach (MazeCell mazeCell in mazePath)
{
canvasPath.Add(new MazeCell(mazeCell.X - 1, mazeCell.Y - 1, mazeCell.Character));
canvasPath[0].IsVisited = mazeCell.IsVisited;
}
mazePath.Clear();
mazePath.AddRange(canvasPath);
StoredMazeArray[ExitCell.Y, ExitCell.X] = ExitCell;
CopyMaze(MazeArray, StoredMazeArray);
CopyMaze(StoredMazeToBeShowed, MazeToBeShowed);
MazeQueue.Clear();
}
if (mazePath != null)
{
CellsInMazePath = mazePath.Count;
}
}
public void SolveMazeMultipleExits(MazeCell[,] mazeArray)
{
InitializeMaze(mazeArray);
var storedMazeArray = new MazeCell[mazeArray.GetLength(0), mazeArray.GetLength(1)];
CopyMaze(storedMazeArray, mazeArray);
while (ExitCells.Count != 0)
{
ExitCell = ExitCells.Dequeue();
mazeArray[ExitCell.Y, ExitCell.X].IsVisited = false;
CurrentCell = EntryCell;
var mazePath = FindShortestPath(EntryCell, ExitCell, CurrentCell, MazeQueue, mazeArray);
if (mazePath == null)
{
Console.WriteLine($"Could not find path to {ExitCell}.");
mazeArray[ExitCell.Y, ExitCell.X].Character = 'x';
mazeArray[ExitCell.Y, ExitCell.X].IsVisited = true;
MazeQueue.Clear();
}
else
{
foreach (var mazeCell in mazePath)
{
if (mazeCell.Character != ExitCell.Character)
{
mazeArray[mazeCell.Y, mazeCell.X].Character = '.';
}
else
{
mazeArray[mazeCell.Y, mazeCell.X].Character = '@';
ExitCell.Character = mazeArray[mazeCell.Y, mazeCell.X].Character;
}
DisplayMaze(mazeArray);
}
Console.WriteLine($"Shortest path from {EntryCell} to {ExitCell} found.");
Console.WriteLine();
MazeQueue.Clear();
storedMazeArray[ExitCell.Y, ExitCell.X] = ExitCell;
CopyMaze(mazeArray, storedMazeArray);
}
}
}
private void InitializeMaze(MazeCell[,] mazeArray)
{
foreach (var mazeCell in mazeArray)
{
if (mazeCell.Character == 'm')
{
EntryCell = mazeCell;
CurrentCell = EntryCell;
}
if (mazeCell.Character == 'e')
{
ExitCells.Enqueue(mazeCell);
}
if (mazeCell.Character == '0' || mazeCell.Character == 'm')
{
mazeCell.IsVisited = false;
}
else
{
mazeCell.IsVisited = true;
}
MazeQueue.Clear();
}
}
