def bfs(start, end):
"""
Breadth first search. Takes a start tile and end tile, and uses
their neighbour list to traverse.
Uses the LIFO queue in queues.py.
:param start: Tile
:param end: Tile
:return: came_from, dictionary with all tiles, and where we came from (parent).
success, True or False. If the algorithm found the end tile or not.
has_been_next, list over tiles that has been considered as the next tile.
"""
frontier = Queue()
frontier.add(start)
came_from = {start: None}
success = False
has_been_next = []
while not frontier.empty():
current = frontier.pop()
current.visit()
if current == end:
print("Breadth First Search, successful.")
success = True
break
for next_tile in current.neighbours:
if next_tile not in has_been_next:
has_been_next.append(next_tile)
if next_tile not in came_from:
frontier.add(next_tile)
came_from[next_tile] = current
return came_from, success, has_been_next
def test_queues(self):
q = Queue()
for i in range(1,100):
q.push(i)
self.assertEqual(99,q.size())
self.assertEqual(1,q.peek())
self.assertEqual(1,q.pop())