Update python_pathfinder.py

python_pathfinder.py

@@ -1,59 +1,39 @@
-# This function reads in a maze from a file and returns it as a list of lists of integers.
-# Each integer corresponds to a different type of cell in the maze.
-# 0 = empty cell
-# 1 = wall
-# 3 = end of the maze
-# 5 = start of the maze
+#code has been optimised to run faster using less caching and more direct functions
+from collections import deque
+
 def load_maze(filename):
     with open(filename, "r") as file:
         maze = [[int(num) for num in line.strip().split(",")] for line in file]
         if len(maze) == 0:
             print("Maze Not loaded.")
     return maze
 
-# This function takes in a maze and returns the coordinates of the start and end points.
-# It searches the maze for the first occurrence of a 5 (start) and a 3 (end) and returns their coordinates as a tuple.
-# If either the start or end point is not found, None is returned.
 def find_start_and_end(maze):
-    rows = len(maze)
-    cols = len(maze[0])
     start = None
     end = None
-    for i in range(rows):
-        for j in range(cols):
-            if maze[i][j] == 5:
+    for i, row in enumerate(maze):
+        for j, cell in enumerate(row):
+            if cell == 5:
                 start = (i, j)
-            elif maze[i][j] == 3:
+            elif cell == 3:
                 end = (i, j)
-            # If both start and end points have been found, return them as a tuple.
-            if start != None and end != None:
+            if start and end:
                 return start, end
 
-# This function takes in a maze and finds the shortest path from the start to the end point using BFS.
-# It returns a list of coordinates representing the path from start to end.
-# If no path is found, it returns None.
 def solve_maze(maze):
-    # Find the start and end positions in the maze
     start, end = find_start_and_end(maze)
-    # Get the number of rows and columns in the maze
     rows = len(maze)
     cols = len(maze[0])
-    # Initialize visited and parent 2D arrays to keep track of visited cells and their parents.
-    visited = [[False for j in range(cols)] for i in range(rows)]
-    parent = [[None for j in range(cols)] for i in range(rows)]
-    # Initialize the queue with the start cell and mark it as visited.
-    queue = [start]
-    # Mark the starting position as visited
-    visited[start[0]][start[1]] = True
-    # While the queue is not empty, continue BFS.
+    visited = set()
+    parent = [[None for _ in range(cols)] for _ in range(rows)]
+    queue = deque([start])
+    visited.add(start)
     while queue:
-        current = queue.pop(0)
-        # If the current position is the end position, break out of the loop
+        current = queue.popleft()
         if current == end:
             break
         row, col = current
         neighbors = []
-        # Check if the neighboring positions are valid and not blocked
         if row > 0 and maze[row - 1][col] != 1:
             neighbors.append((row - 1, col))
         if row < rows - 1 and maze[row + 1][col] != 1:
@@ -62,16 +42,13 @@ def solve_maze(maze):
             neighbors.append((row, col - 1))
         if col < cols - 1 and maze[row][col + 1] != 1:
             neighbors.append((row, col + 1))
-        # For each unvisited neighbor, add it to the queue, mark it as visited, and set its parent to the current cell.
         for neighbor in neighbors:
-            if not visited[neighbor[0]][neighbor[1]]:
+            if neighbor not in visited:
                 queue.append(neighbor)
-                visited[neighbor[0]][neighbor[1]] = True
+                visited.add(neighbor)
                 parent[neighbor[0]][neighbor[1]] = current
-    # If the end point has no parent, it means no path was found, so return None.
     if parent[end[0]][end[1]] is None:
         return None
-    # Construct the path from start to end by backtracking from the end position
     path = []
     current = end
     while current != start:
@@ -82,13 +59,10 @@ def solve_maze(maze):
     return path
 
 def print_maze(maze):
-# Prints the maze as a grid of numbers
     for row in maze:
         print(" ".join(str(num) for num in row))
 
 def print_solution(maze, path):
-# Prints the maze with the solution path marked as 5's.
-# Walls are represented by 1's and the end point is a 3.
     for i in range(len(maze)):
         for j in range(len(maze[0])):
             if maze[i][j] == 1:
@@ -98,18 +72,4 @@ def print_solution(maze, path):
             elif (i, j) in path:
                 print("5", end=" ")
             else:
-                print("0", end=" ")
-        print()
-
-def main():
-    filename = "test_maze.txt"
-    maze = load_maze(filename)
-    path = solve_maze(maze)
-    if path != None:
-        print("Solution: ")
-        print_solution(maze, path)
-    else:
-        print("No solution found")
-
-if __name__ == "__main__":
-    main()
+                print("0", end