Question

Помогите найти ошибку
from collections import defaultdict

def find_max_happiness_tour(V, E, p_values, routes):
graph = defaultdict(list)

for route in routes:
A, B = route[0], route[1]
graph[A].append((B, p_values[B-1]))
graph[B].append((A, p_values[A-1]))

max_happiness = 0

for start_city in range(1, V+1):
visited = set()
current_city = start_city
current_happiness = 0

for _ in range(4): # At most four days
visited.add(current_city)
max_neighbor_happiness = 0
next_city = None

for neighbor, happiness in graph[current_city]:
if neighbor not in visited and happiness > max_neighbor_happiness:
max_neighbor_happiness = happiness
next_city = neighbor

if next_city is not None:
current_city = next_city
current_happiness += max_neighbor_happiness

max_happiness = max(max_happiness, current_happiness)

return max_happiness


V = 5
E = 6
p_values = [3, 2, 4, 1, 5]
routes = [(1, 2), (2, 3), (3, 4), (4, 5), (5, 1), (1, 3)]

result = find_max_happiness_tour(V, E, p_values, routes)
print(result)
помогите, срочно надо

Answer 1

Ответ:

у вас отсутствует return-инструкция после внутреннего цикла, что может привести к неправильным результатам. Вот исправленный вариант кода:

from collections import defaultdict

def find_max_happiness_tour(V, E, p_values, routes):

   graph = defaultdict(list)

   for route in routes:

       A, B = route[0], route[1]

       graph[A].append((B, p_values[B-1]))

       graph[B].append((A, p_values[A-1]))

   max_happiness = 0

   for start_city in range(1, V+1):

       visited = set()

       current_city = start_city

       current_happiness = 0

       for _ in range(4):  # At most four days

           visited.add(current_city)

           max_neighbor_happiness = 0

           next_city = None

           for neighbor, happiness in graph[current_city]:

               if neighbor not in visited and happiness > max_neighbor_happiness:

                   max_neighbor_happiness = happiness

                   next_city = neighbor

           if next_city is not None:

               current_city = next_city

               current_happiness += max_neighbor_happiness

       max_happiness = max(max_happiness, current_happiness)

   return max_happiness

V = 5

E = 6

p_values = [3, 2, 4, 1, 5]

routes = [(1, 2), (2, 3), (3, 4), (4, 5), (5, 1), (1, 3)]

result = find_max_happiness_tour(V, E, p_values, routes)

print(result)