import itertools with open("input") as f: connections = [n.strip() for n in f.readlines()] GRAPH = dict() LOCATIONS = set() for connection in connections: [location_a, _, location_b, _, distance] = connection.split(" ") distance = int(distance) LOCATIONS.add(location_a) LOCATIONS.add(location_b) GRAPH[(location_a, location_b)] = distance GRAPH[(location_b, location_a)] = distance def calculate_distance(route): dist = 0 for i in range(len(route) - 1): location_a = route[i] location_b = route[i + 1] if (location_a, location_b) not in GRAPH: return None dist += GRAPH[(location_a, location_b)] return dist LONGEST_ROUTE = None LONGEST_DISTANCE = None for route in itertools.permutations(LOCATIONS, len(LOCATIONS)): dist = calculate_distance(route) if dist is None: continue if LONGEST_DISTANCE is None or dist > LONGEST_DISTANCE: LONGEST_DISTANCE = dist LONGEST_ROUTE = route print(LONGEST_ROUTE) print(LONGEST_DISTANCE)