def breadth_first_search(self): """ Breadth-first search. @rtype: list @return: Generated spanning_tree """ return searching.breadth_first_search(self)
def breadth_first_search(self): """ Breadth-first search. @rtype: dictionary @return: Generated spanning_tree """ return searching.breadth_first_search(self)
def main():
st = time.perf_counter() #Start a time counter.
if len(sys.argv) == 4: #If the length of the keyword arguments is four...
method = sys.argv[
1] #The second argument is the method/algorithm used to find a solution.
input_file = sys.argv[
2] #The third argument is a .txt file containing the initial and final state of the problem.
output_file = sys.argv[
3] #The fourth argument is a .txt file containing the solution of the problem.
initial_state, goal_state = read_input_file(
filename=input_file
) #Read the input file and return two state objects.
if method == 'breadth': #Check which method is selected and solve the problem accordingly.
solution = breadth_first_search(current_state=initial_state,
goal_state=goal_state,
timeout=300)
elif method == 'depth':
solution = depth_first_search(current_state=initial_state,
goal_state=goal_state,
timeout=300)
elif method == 'best':
solution = heuristic_search(current_state=initial_state,
goal_state=goal_state,
method='best',
timeout=300)
elif method == 'astar':
solution = heuristic_search(current_state=initial_state,
goal_state=goal_state,
method='astar',
timeout=300)
else: #If the method argument is none of the above, print a usage message.
solution = None
print(
'Usage: python bw.py <method> <input filename> <output filename>'
)
if solution == goal_state: #If the solution is equal to the goal state...
number_of_moves = write_output_file(
solution=solution, filename=output_file
) #Write the solution file and return the number of moves.
print('Solution found!')
print('Number of blocks:', len(initial_state.layout.keys()))
print('Method:', method)
print('Number of moves:', number_of_moves)
print('Execution time:', str(round(time.perf_counter() - st, 4)))
else: #Else, if the length of the keyword arguments is not equal to four, print a usage message.
print(
'Usage: python bw.py <method> <input filename> <output filename>')
def breadth_first_search(self, root=None): """ Breadth-first search. @type root: node @param root: Optional root node (will explore only root's connected component) @rtype: dictionary @return: A tuple containing a dictionary and a list. 1. Generated spanning tree 2. Graph's level-based ordering """ return searching.breadth_first_search(self, root)
def test_bfs(self):
"""Test and visualize breadth-first search"""
start = 'a'
goal = 'u'
node_positions = {
n: self.romania.node[n]['pos']
for n in self.romania.node.keys()
}
self.romania.reset_search()
path = breadth_first_search(self.romania, start, goal)
self.draw_graph(self.romania,
node_positions=node_positions,
start=start,
goal=goal,
path=path)
