def GFS(graph: Graph, starting_node_id, target_id, callback, steps_counter):
_adjacency_dict = graph.get_adjacency_dict()
visited_nodes = list()
next = starting_node_id
backtrack_index = -1
while next != target_id:
steps_counter() # for each node traversal count the steps
children = list() # TODO make it an actual list from the 2 conditions
if next != None: # if it's not stuck
callback(graph.nodes[next])
visited_nodes.append(next)
children = [x[0] for x in _adjacency_dict[next]]
else: # if it is stuck
backtrack_index = -2
# start from the second to last one (the before the stuck)
current = visited_nodes[backtrack_index]
visited_nodes.append(visited_nodes[backtrack_index])
while not has_unvisited_child(_adjacency_dict, current,
visited_nodes):
# callback(graph.nodes[current])
backtrack_index -= 2
current = visited_nodes[backtrack_index]
visited_nodes.append(visited_nodes[backtrack_index])
callback(graph.nodes[visited_nodes[backtrack_index]])
callback(graph.nodes[current])
children = [x[0] for x in _adjacency_dict[current]]
next = get_the_closet_to_target_child(graph, children, target_id,
visited_nodes)
callback(graph.nodes[target_id])
def BFS(graph: Graph, starting_node_id, callback, steps_counter):
"""
Do a BFS over a graph
NOTE: callback is a function that gets called after each node being visited
NOTE: callback is expected to take a Node object only as an argument
"""
visited_nodes = set()
adjacency_dict = graph.get_adjacency_dict()
nodes_queue = [starting_node_id]
while len(nodes_queue):
node = nodes_queue.pop(0) # remove the first element, FIFO
if node not in visited_nodes:
visited_nodes.add(node)
connections = adjacency_dict.get(node)
nodes_list = [node]
nodes_list.extend(connections)
callback(nodes_list)
steps_counter()
if connections:
for connection in connections:
# add the to index to nodes queue
nodes_queue.append(connection[0])
def DFS(graph: Graph, starting_node_id):
""" Do a DFS over a graph """
target_node_ids = [node.id for node in graph.nodes if node.is_target()]
adjacency_dict = graph.get_adjacency_dict()
return lazyDFS_many(starting_node_id, target_node_ids, adjacency_dict)