private List <MazeCell> FindLongestPath(MazeCell currentCell, MazeCell exitCell, MazeCell[,] mazeArray)
{
List <MazeCell> longestPath = null;
if (currentCell.Y < 0 || currentCell.X < 0)
{
return(null);
}
if (currentCell.Y == mazeArray.GetLength(0) || currentCell.X == mazeArray.GetLength(1))
{
return(null);
}
if (mazeArray[currentCell.Y, currentCell.X].IsVisited == true)
{
return(null);
}
if (currentCell.Character == exitCell.Character)
{
var longPath = new List <MazeCell>();
longPath.Add(currentCell);
return(longPath);
}
mazeArray[currentCell.Y, currentCell.X].IsVisited = true;
var nextCells = new List <MazeCell>();
if (mazeArray[currentCell.Y - 1, currentCell.X].IsVisited == false)
{
nextCells.Add(mazeArray[currentCell.Y - 1, currentCell.X]);
}
if (mazeArray[currentCell.Y + 1, currentCell.X].IsVisited == false)
{
nextCells.Add(mazeArray[currentCell.Y + 1, currentCell.X]);
}
if (mazeArray[currentCell.Y, currentCell.X - 1].IsVisited == false)
{
nextCells.Add(mazeArray[currentCell.Y, currentCell.X - 1]);
}
if (mazeArray[currentCell.Y, currentCell.X + 1].IsVisited == false)
{
nextCells.Add(mazeArray[currentCell.Y, currentCell.X + 1]);
}
var maxLength = -1;
foreach (var nextCell in nextCells)
{
var longPath = FindLongestPath(nextCell, exitCell, mazeArray);
if (longPath != null && longPath.Count > maxLength)
{
maxLength = longPath.Count;
longPath.Add(currentCell);
longestPath = longPath;
}
}
mazeArray[currentCell.Y, currentCell.X].IsVisited = false;
if (longestPath == null || longestPath.Count == 0)
{
return(null);
}
return(longestPath);
}
static void Main(string[] args)
{
string wall = "";
string input = "";
var MazeSolver = new MazeSolverUsingStack();
bool done = false;
Console.WriteLine("It is assumed that the user knows each row has a fixed number of characters and only 1 mouse can be in the maze.");
Console.WriteLine("Create a maze by inputting a string of walls, paths, exits, and 1 mouse.");
Console.WriteLine();
Console.ReadLine();
Console.Clear();
while (done != true)
{
Console.WriteLine("Legend: e - exit");
Console.WriteLine("Legend: n - mouse");
Console.WriteLine("Legend: 0 - path");
Console.WriteLine("Legend: 1 - wall");
Console.WriteLine("Enter Row: ");
input = Console.ReadLine();
input = "1" + input + "1";
if (MazeSolver.MazeRows.Count == 0)
{
var mazerowstacklength = input.Length;
for (int x = 0; x < mazerowstacklength; x++)
{
wall += "1";
}
MazeSolver.MazeRows.Push(wall);
}
MazeSolver.MazeRows.Push(input);
Console.WriteLine("Would you like to enter another row? (Y or N)");
var answer = Console.ReadLine().ToLowerInvariant();
if (answer == "n")
{
done = true;
}
Console.WriteLine();
}
Console.Clear();
MazeSolver.MazeRows.Push(wall);
MazeCell[,] mazeArray = new MazeCell[MazeSolver.MazeRows.Count, input.Length];
for (int y = MazeSolver.MazeRows.Count - 1; y >= 0; y--)
{
var currentRow = MazeSolver.MazeRows.Pop();
for (int x = 0; x < input.Length; x++)
{
mazeArray[y, x] = new MazeCell(x, y, currentRow[x]);
}
}
MazeSolver.DisplayMaze(mazeArray);
var exitCount = 0;
foreach (var mazeCell in mazeArray)
{
if (mazeCell.Character == 'e')
{
exitCount++;
}
}
//if (exitCount > 1)
//{
// MazeSolver.SolveMazeMultipleExits(mazeArray);
//}
//else
//{
// MazeSolver.SolveMazeOneExit(mazeArray);
//}
MazeSolver.SolveMazeMultipleExits(mazeArray);
Console.ReadLine();
}
public void SolveMazeMultipleExitsOld(MazeCell[,] mazeArray)
{
bool NotEntryCell = false;
//ExitCellCount = 0;
var foundExitCells = 0;
InitializeMaze(mazeArray);
bool ExitMethodFlag = false;
if (ExitCells.Count > 1)
{
Console.WriteLine("Would you like to continue search from last exit found(1), or start from entrance(2)?");
var answer = Console.ReadLine();
if (answer == "1")
{
ExitMethodFlag = true;
}
}
CurrentCell = EntryCell;
var storedMazeArray = new MazeCell[mazeArray.GetLength(0), mazeArray.GetLength(1)];
for (int y = 0; y < mazeArray.GetLength(0); y++)
{
for (int x = 0; x < mazeArray.GetLength(1); x++)
{
storedMazeArray[y, x] = new MazeCell(mazeArray[y, x].X, mazeArray[y, x].Y, mazeArray[y, x].Character);
}
}
while (foundExitCells != ExitCells.Count)
{
if (NotEntryCell == false)
{
NotEntryCell = true;
}
else
{
if (CurrentCell.Character == 'e')
{
foundExitCells++;
storedMazeArray[CurrentCell.Y, CurrentCell.X].Character = '@';
mazeArray = new MazeCell[mazeArray.GetLength(0), mazeArray.GetLength(1)];
for (int y = 0; y < mazeArray.GetLength(0); y++)
{
for (int x = 0; x < mazeArray.GetLength(1); x++)
{
mazeArray[y, x] = new MazeCell(storedMazeArray[y, x].X, storedMazeArray[y, x].Y, storedMazeArray[y, x].Character);
}
}
Console.WriteLine("Refreshed array");
if (ExitMethodFlag == true)
{
CurrentCell = mazeArray[CurrentCell.Y, CurrentCell.X];
MazeStack = new Stack <MazeCell>();
}
else
{
CurrentCell = mazeArray[EntryCell.Y, EntryCell.X];
MazeStack = new Stack <MazeCell>();
}
}
else
{
CurrentCell.Character = '.';
}
}
if (mazeArray[CurrentCell.Y + 1, CurrentCell.X].Character == '0' || mazeArray[CurrentCell.Y + 1, CurrentCell.X].Character == 'e')
{
MazeStack.Push(mazeArray[CurrentCell.Y + 1, CurrentCell.X]);
}
if (mazeArray[CurrentCell.Y - 1, CurrentCell.X].Character == '0' || mazeArray[CurrentCell.Y - 1, CurrentCell.X].Character == 'e')
{
MazeStack.Push(mazeArray[CurrentCell.Y - 1, CurrentCell.X]);
}
if (mazeArray[CurrentCell.Y, CurrentCell.X - 1].Character == '0' || mazeArray[CurrentCell.Y, CurrentCell.X - 1].Character == 'e')
{
MazeStack.Push(mazeArray[CurrentCell.Y, CurrentCell.X - 1]);
}
if (mazeArray[CurrentCell.Y, CurrentCell.X + 1].Character == '0' || mazeArray[CurrentCell.Y, CurrentCell.X + 1].Character == 'e')
{
MazeStack.Push(mazeArray[CurrentCell.Y, CurrentCell.X + 1]);
}
DisplayMaze(mazeArray);
if (MazeStack.Count <= 0)
{
if (foundExitCells > 0)
{
Console.WriteLine("Only " + foundExitCells +
" were/was found. Other exits are unreachable.");
}
else
{
Console.WriteLine("Unsolvable maze.");
}
break;
}
else
{
CurrentCell = MazeStack.Pop();
}
}
}