/// <summary>
/// Displays the final path taken from start to finish in the maze
/// </summary>
/// <param name="row">Row's of the maze board for displaying</param>
/// <param name="col">Column's of the maze board for displaying</param>
/// <param name="node">Array holding the Maze data</param>
public static void ShowFinalPath(int row, int col, LinkedNode[,] node)
{
// While the final path stack is not empty
while (final_path.Count != 0)
{
// Pop and access the current node / section of the board that was traversed
LinkedNode curr = final_path.Pop();
// Change the value from V for visited to F for found
if (curr.val == 'v')
{
curr.val = 'F';
}
}
// Display the maze and prompt the user
ShowMaze(row, col, node);
Console.WriteLine("Here is the path taken! (labelled F for Found)");
}
public static Stack <LinkedNode> final_path = new Stack <LinkedNode>(); // Stack to keep track of the path taken from start to end
/// <summary>
/// Maze Traversal Function that traverses through the maze and finds an exit,
/// this traversal will backtrack and take another available path if the user arrives at a dead end
/// </summary>
/// <param name="row">Row's of the maze board for displaying</param>
/// <param name="col">Columns of the maze board for displaying</param>
/// <param name="startX">Start position X coordinate</param>
/// <param name="startY">Start position Y coordinate</param>
/// <param name="Maze">Array containing the maze data</param>
/// <returns>STATUS: The final result showing whether or not the exit of the maze was found </returns>
public static bool StackTraverseMaze(int row, int col, int startX, int startY, LinkedNode[,] Maze)
{
bool STATUS = false;
// Stack to progress through the maze
Stack <LinkedNode> path = new Stack <LinkedNode>();
// Push the starting node onto the path stack
path.Push(Maze[startX, startY]);
// While the path stack is not empty - While there are available steps
while (path.Count != 0)
{
LinkedNode currentNode = path.Pop(); // Pop the stack to access the current node
// If current node is valid but not the starting node
if (currentNode.val != 's' && currentNode.val == '0' && currentNode.val != 'e')
{
currentNode.val = 'v';
}
// Show maze to the user each iteration
ShowMaze(row, col, Maze);
// If current node is the exit
if (currentNode.val == 'e')
{
STATUS = true; // SUCCESS
break; // Exit the loop
}
// Check neighbors for valid square
// - Try catch used to avoid null reference exception incase the program needs to assess a neighbor that might be null
// Check top neighbor
try
{
// If valid or the exit
if (currentNode.top.val == '0' || currentNode.top.val == 'e')
{
path.Push(currentNode.top); // Push neighbor - move to valid square
final_path.Push(currentNode.top); // Push - has been visited
continue; // Progress to Next iteration
}
}
catch (NullReferenceException nre) { } // Handle if neighbor that is being accessed is null
// Check below neighbor
try
{
// If valid or the exit
if (currentNode.bottom.val == '0' || currentNode.bottom.val == 'e')
{
path.Push(currentNode.bottom); // Push neighbor - move to valid square
final_path.Push(currentNode.bottom); // Push - has been visited
continue; // Progress to Next iteration
}
}
catch (NullReferenceException nre) { } // Handle if neighbor that is being accessed is null
// Check left neighbor
try
{
// If valid or the exit
if (currentNode.prev.val == '0' || currentNode.prev.val == 'e')
{
path.Push(currentNode.prev); // Push neighbor - move to valid square
final_path.Push(currentNode.prev); // Push - has been visited
continue; // Progress to Next iteration
}
}
catch (NullReferenceException nre) { } // Handle if neighbor that is being accessed is null
// Check right neighbor
try
{
// If valid or the exit
if (currentNode.next.val == '0' || currentNode.next.val == 'e')
{
path.Push(currentNode.next); // Push neighbor - move to valid square
final_path.Push(currentNode.next); // Push - has been visited
continue; // Progress to Next iteration
}
}
catch (NullReferenceException nre) { } // Handle if neighbor that is being accessed is null
// BACKTRACK IF CURRENT NODE HAS NO AVAILABLE '0' / valid steps
// If the current node is at a deadend - then check for visited squares
// Check below
if (currentNode.bottom.val == 'v')
{
// Push, move to that node
path.Push(currentNode.bottom);
final_path.Pop(); // Pop as the previously stored final node is no longer necessary
continue; // Progress to Next iteration
}
// Check above
if (currentNode.top.val == 'v')
{
// Push, move to that node
path.Push(currentNode.top);
final_path.Pop(); // Pop as the previously stored final node is no longer necessary
continue; // Progress to Next iteration
}
// Check Left
if (currentNode.prev.val == 'v')
{
// Push, move to that node
path.Push(currentNode.prev);
final_path.Pop(); // Pop as the previously stored final node is no longer necessary
continue;
}
// Check right
if (currentNode.next.val == 'v')
{
// Push, move to that node
path.Push(currentNode.next);
final_path.Pop(); // Pop as the previously stored final node is no longer necessary
continue;
}
}
return(STATUS); // Return result of the traversal
}
static void Main(string[] args)
{
//path to the file. This file you could read from the command line
// Takes a commandline argument for a file - files must be in the same directory as the executable
Console.Write("Please enter a maze file: ");
string path = Console.ReadLine();
string[] lines = System.IO.File.ReadAllLines(path);
//First line holds row and column information
string[] line = lines[0].Split(' ');
int row = Convert.ToInt32(line[0]);
int col = Convert.ToInt32(line[1]);
//holding 0s 1s and starting point 's' and exit point 'o'
char[,] maze_board = new char[row, col];
for (int i = 1; i < lines.Length; i++)
{
//String to char array
char[] arr = lines[i].ToCharArray();
for (int j = 0; j < arr.Length; j++)
{
maze_board[i - 1, j] = arr[j];
}
}
//Display the maze now
Console.WriteLine("Here is the maze you have chosen...");
Console.WriteLine();
for (int i = 0; i < row; i++)
{
for (int j = 0; j < col; j++)
{
Console.Write(maze_board[i, j] + " ");
}
Console.WriteLine();
//Console.WriteLine();
}
//An array of nodes to create a four-way linked list for traversal of the maze
LinkedNode[,] node = new LinkedNode[row, col];
//Holds the start coords of the maze entrance
int startX = -1, startY = -1;
//Nested for loops that index and populate a 2d dimensional array which will be the maze
for (int i = 0; i < lines.Length - 1; i++)
{
//Converts the maze file to an array of characters
char[] arr = lines[i + 1].ToCharArray();
for (int j = 0; j < arr.Length; j++)
{
//Sets the array of nodes to be the number of tiles in the maze
node[i, j] = new LinkedNode(arr[j]);
//If the start of the maze is found, store the array coordinates
if (node[i, j].val == 's' || node[i, j].val == 'o')
{
startX = i;
startY = j;
}
//Checks that the left side of the maze tile is inside the array bounds
if (j - 1 >= 0)
{
//creates a link between the previous and next nodes
node[i, j].prev = node[i, j - 1];
node[i, j - 1].next = node[i, j];
}
//Does the same but with the top and bottom tiles
if (i - 1 >= 0)
{
node[i, j].top = node[i - 1, j];
node[i - 1, j].bottom = node[i, j];
}
}
}
// Run the stack traversal of the maze and recieve the final outcome
bool result = LinkedNode.StackTraverseMaze(row, col, startX, startY, node);
// If the final result is true - success
if (result == true)
{
// Prompt the user
Console.WriteLine("Congrats, Maze is solved");
// Show the final path taken from start to exit
LinkedNode.ShowFinalPath(row, col, node);
}
// If false - fail
else
{
Console.WriteLine("UH OHHHH!!! The maze has not been solved..."); // Prompt the user
}
}