def a_star(graph, visited, wait_list):
while True:
try:
node = wait_list.pop(0)
visited.append(node)
if node.v == '.':
bfs_mark_path(node)
return True
elif node.v == '%':
continue
else:
neighbor=graph_fun.get_neighbor(graph, node)
for one in neighbor:
if one not in visited:
if one not in wait_list:
one.save_parent(node)
one.update_g(node.g+1)
one.update_f()
wait_list.append(one)
else:
if one.g<node.g+1:
one.save_parent(node)
one.update_g(node.g+1)
one.update_f()
wait_list.sort(key=operator.attrgetter('f'))
except IndexError:
print "Sorry! Cannot find a path to the end!"
return False
def dfs(graph, visited, node):
visited.append(node)
if node.v=='%':
return False
neighbor = graph_fun.get_neighbor(graph, node)
for one in neighbor:
if one not in visited:
if one.v=='.':
return True
else:
if dfs(graph, visited, one):
one.update_value('.')
return True
return False
def greedy_bfs(graph, visited, node):
if node.v == '.':
return True
elif node.v == '%':
return False
else:
visited.append(node)
neighbor = graph_fun.get_neighbor(graph, node)
neighbor.sort(key=operator.attrgetter('h'))
for one in neighbor:
if one not in visited:
if greedy_bfs(graph, visited, one):
node.update_value('.')
return True
return False
def bfs(graph, visited, queue):
while True:
try:
node = queue.popleft()
visited.append(node)
if node.v=='.':
bfs_mark_path(node)
return True
elif node.v=='%':
continue
else:
neighbor = graph_fun.get_neighbor(graph, node)
#add new nodes to the queue
for one in neighbor:
if one not in visited:
if one not in queue:
one.save_parent(node)
queue.append(one)
except IndexError:
print "Sorry! Cannot find a path to the end!"
return False
