Seeking advise on how structure python to create a maze, solve it with BFS and to have basic navigation within maze with number of moves required to navigate. Use move along the path, Up, Left, Right, Down. Below is some code that I mangled together to think about and figure how to structure python for this BFS algorithm code.
Is anyone open to mentoring on this BFS algorithm navigation maze python structure?
To basically follow the following algorithm:
function BREADTH-FIRST-SEARCH(problem) returns a solution node or failure node ← NODE(problem.INITIAL) if problem.IS-GOAL(node.STATE) then return node frontier ← a FIFO queue, with node as an element reached ← {problem.INITIAL} while not IS-EMPTY(frontier ) do node ← POP(frontier ) for each child in EXPAND(problem, node) do s ← child.STATE if problem.IS-GOAL(s) then return child if s is not in reached then add s to reached add child to frontier return failure
import sys
def parse_map(filename):
with open(filename, "r") as f:
return [[char for char in line] for line in f.read().rstrip("\n").split("\n")][3:]
def count_x(house_map):
return sum([ row.count('p') for row in house_map ] )
def printable_house_map(house_map):
return "\n".join(["".join(row) for row in house_map])
def add_x(house_map, row, col):
return house_map[0:row] + [house_map[row][0:col] + ['p',] + house_map[row][col+1:]] + house_map[row+1:]
def successors(house_map):
return [ add_x(house_map, r, c) for r in range(0, len(house_map)) for c in range(0,len(house_map[0])) if house_map[r][c] == '.' ]
def is_goal(house_map, k):
return count_x(house_map) == k
def bfs_graph_search(house_map):
fringe = [initial_house_map]
if house_map.goal_test(node.state):
return fringe
fringe = deque([house_map])
visited = set()
while fringe:
fringe = fringe.popleft()
visited.add(node.state)
for child in node.expand(problem):
if child.state not in fringe and child not in visited:
if house_map.goal_test(child.state):
return child
fringe.append(child)
return None
def solve(initial_house_map,k):
fringe = [initial_house_map]
while len(fringe) > 0:
for new_house_map in successors( fringe.pop() ):
if is_goal(new_house_map,k):
return(new_house_map,True)
fringe.append(new_house_map)
if __name__ == "__main__":
house_map=parse_map('map1.txt')
k = 2
print ("Initial ]house map:\n" + printable_house_map(house_map) + "\n\nSearching for solution...\n")
solution = solve(house_map,k)
print ("Found:")
print (printable_house_map(solution[0]) if solution[1] else "False")
class Agent:
def __init__(self, initial, goal=None):
self.initial = initial
self.goal = goal
def actions(self, state):
raise NotImplementedError
def result(self, state, action):
raise NotImplementedError
def goal_test(self, state):
if isinstance(self.goal, list):
return is_in(state, self.goal)
else:
return state == self.goal
def path_cost(self, c, state1, action, state2):
return c + 1
def value(self, state):
raise NotImplementedError
class FringeGraph:
def __init__(self, state, parent=None, action=None, path_cost=0):
self.state = state
self.parent = parent
self.action = action
self.path_cost = path_cost
self.depth = 0
if parent:
self.depth = parent.depth + 1
def path(self):
node, path_back = self, []
while node:
path_back.append(node)
node = node.parent
return list(reversed(path_back))
def solution(self):
return [node.action for node in self.path()[1:]]
def expand(self, agent):
return [self.child_node(agent, action)
for action in agent.actions(self.state)]
def child_node(self, agent, action):
next_state = agent.result(self.state, action)
next_node = Node(next_state, self, action, problem.path_cost(self.path_cost, self.state, action, next_state))
return next_node
class Agent:
def __init__(self, initial, goal=None):
self.initial = initial
self.goal = goal
def actions(self, state):
raise NotImplementedError
def result(self, state, action):
raise NotImplementedError
def goal_test(self, state):
if isinstance(self.goal, list):
return is_in(state, self.goal)
else:
return state == self.goal
def path_cost(self, c, state1, action, state2):
return c + 1
def value(self, state):
raise NotImplementedError
class FringeGraph:
def __init__(self, state, parent=None, action=None, path_cost=0):
self.state = state
self.parent = parent
self.action = action
self.path_cost = path_cost
self.depth = 0
if parent:
self.depth = parent.depth + 1
def path(self):
node, path_back = self, []
while node:
path_back.append(node)
node = node.parent
return list(reversed(path_back))
def solution(self):
return [node.action for node in self.path()[1:]]
def expand(self, agent):
return [self.child_node(agent, action)
for action in agent.actions(self.state)]
def child_node(self, agent, action):
next_state = agent.result(self.state, action)
next_node = Node(next_state, self, action, agent.path_cost(self.path_cost, self.state, action, next_state))
return next_node