Initial commit

Path_Finding_L2.py

@@ -0,0 +1,146 @@
+import sys
+
+class Node():
+    def __init__(self, state, parent, action):
+        self.state = state
+        self.parent = parent
+        self.action = action
+
+class StackFrontier():
+    def __init__(self):
+        self.frontier = []
+
+    def add(self, node):
+        self.frontier.append(node)
+
+    def contains_state(self, state):
+        return any(node.state == state for node in self.frontier)
+
+    def empty(self):
+        return len(self.frontier) == 0
+
+    def remove(self):
+        if self.empty():
+            raise Exception("empty frontier")
+        else:
+            node = self.frontier[-1]
+            self.frontier = self.frontier[:-1]
+            return node
+
+class QueueFrontier(StackFrontier):
+
+    def remove(self):
+        if self.empty():
+            raise Exception("empty frontier")
+        else:
+            node = self.frontier[0]
+            self.frontier = self.frontier[1:]
+            return node
+
+class Maze():
+
+    def __init__(self, filename):
+
+        # Read file and set height and width of maze
+        with open(filename) as f:
+            contents = f.read()
+
+        # Validate start and goal
+        if contents.count("A") != 1:
+            raise Exception("maze must have exactly one start point")
+        if contents.count("B") != 1:
+            raise Exception("maze must have exactly one goal")
+
+        # Determine height and width of maze
+        contents = contents.splitlines()
+        self.height = len(contents)
+        self.width = max(len(line) for line in contents)
+
+        # Keep track of walls
+        self.walls = []
+        for i in range(self.height):
+            row = []
+            for j in range(self.width):
+                try:
+                    if contents[i][j] == "A":
+                        self.start = (i, j)
+                        row.append(False)
+                    elif contents[i][j] == "B":
+                        self.goal = (i, j)
+                        row.append(False)
+                    elif contents[i][j] == " ":
+                        row.append(False)
+                    else:
+                        row.append(True)
+                except IndexError:
+                    row.append(False)
+            self.walls.append(row)
+
+        self.solution = None
+
+
+    def print(self):
+            """
+        Prints the maze to the console, displaying walls, the start and goal positions, 
+        and the solution path if it exists.
+
+        The method uses different characters to represent various elements in the maze:
+        - '█' for walls
+        - 'A' for the start position
+        - 'B' for the goal position
+        - '*' for the solution path, if available
+        - ' ' for open spaces
+
+        If a solution has been found, the path from the start to the goal will be shown
+        with asterisks ('*').
+
+        Returns:
+            None
+        """
+            raise NotImplementedError("neighbors method is not implemented yet")
+
+
+    def neighbors(self, state):
+              """
+        Returns a list of neighboring states in the maze that can be reached 
+        from the current state.
+
+        Args:
+            state (tuple): The current position in the maze as (row, col).
+
+        Returns:
+            list: A list of tuples representing neighboring positions 
+                  that can be moved to.
+        """
+              raise NotImplementedError("neighbors method is not implemented yet")
+
+
+    def solve(self):
+        """
+        Finds a solution to the maze using breadth-first search (BFS) if one exists.
+
+        Returns:
+            None: Modifies the class attributes to store the solution path 
+                  and number of states explored.
+        """
+
+        raise NotImplementedError("solve method is not implemented yet")
+
+
+    def output_image(self, filename, show_solution=True, show_explored=False):
+        raise NotImplementedError("output_image method is not implemented yet")
+
+
+if len(sys.argv) != 2:
+    sys.exit("Usage: python Path_Finding_L2.py maze.txt")
+
+m = Maze(sys.argv[1])
+print("Maze:")
+m.print()
+print("Solving...")
+m.solve()
+print("States Explored:", m.num_explored)
+print("Solution:")
+m.print()
+#m.output_image("maze.png", show_explored=True)
+