G = Graph.fromfile(io.filein)
# later defined source and destination vertexes
s = 0
t = 0
# Floyd-Warshall's part
io.section('Floyd-Warshall\'s algorithm')
search_results = algorithm.floyd_warshall(G)
if search_results is None:
io.print('Cannot find distance using Floyd-Warshall - negative cycles are '
'present')
else:
# print distance matrix
io.print('Distance matrix: ')
io.print_matrix(algorithm.distance_matrix(search_results), 's\\t')
# ask user for source and destination vertexes
s = userio.readvertex(G.V(), 'source')
t = userio.readvertex(G.V(), 'destination')
# print path from s to t
path = algorithm.forwardtrace_path_from_all_to_all(search_results, s,
t)
if path is None:
io.print('There is no path from vertex #{} to #{}'.format(s + 1,
t + 1))
else:
io.print('Path from #{} to #{}:'.format(s + 1, t + 1))
io.print_path(path)
