def travel(adj_mat, src=0):
# Start time
start = clock()
optimal_tour = []
n = len(adj_mat)
if not n:
raise ValueError("Invalid adj Matrix")
u = Node()
PQ = PriorityQueue()
optimal_length = 0
v = Node(level=0, path=[0])
min_length = float('inf') # infinity
v.bound = bound(adj_mat, v)
PQ.put(v)
while not PQ.empty():
v = PQ.get()
if v.bound < min_length:
u.level = v.level + 1
for i in filter(lambda x: x not in v.path, range(1, n)):
u.path = v.path[:]
u.path.append(i)
if u.level == n - 2:
l = set(range(1, n)) - set(u.path)
u.path.append(list(l)[0])
# putting the first vertex at last
u.path.append(0)
_len = length(adj_mat, u)
if _len < min_length:
min_length = _len
optimal_length = _len
optimal_tour = u.path[:]
else:
u.bound = bound(adj_mat, u)
if u.bound < min_length:
PQ.put(u)
# make a new node at each iteration! python it is!!
u = Node(level=u.level)
# shifting to proper source(start of path)
optimal_tour_src = optimal_tour
if src is not 1:
optimal_tour_src = optimal_tour[:-1]
y = optimal_tour_src.index(src)
optimal_tour_src = optimal_tour_src[y:] + optimal_tour_src[:y]
optimal_tour_src.append(optimal_tour_src[0])
BnB_time = clock() - start
BnB_output = [
"Branch and Bound", optimal_length, optimal_tour_src, BnB_time
]
#return optimal_tour_src, optimal_length
return BnB_output
def travel(adj_mat, src=0):
optimal_tour = []
n = len(adj_mat)
if not n:
raise ValueError("Invalid adj Matrix")
u = Node()
PQ = PriorityQueue()
optimal_length = 0
v = Node(level=0, path=[0])
min_length = float('inf') # infinity
v.bound = bound(adj_mat, v)
PQ.put(v)
while not PQ.empty():
v = PQ.get()
if v.bound < min_length:
u.level = v.level + 1
for i in filter(lambda x: x not in v.path, range(1, n)):
u.path = v.path[:]
u.path.append(i)
if u.level == n - 2:
l = set(range(1, n)) - set(u.path)
u.path.append(list(l)[0])
# putting the first vertex at last
u.path.append(0)
_len = length(adj_mat, u)
if _len < min_length:
min_length = _len
optimal_length = _len
optimal_tour = u.path[:]
else:
u.bound = bound(adj_mat, u)
if u.bound < min_length:
PQ.put(u)
# make a new node at each iteration! python it is!!
u = Node(level=u.level)
# shifting to proper source(start of path)
optimal_tour_src = optimal_tour
if src is not 1:
optimal_tour_src = optimal_tour[:-1]
y = optimal_tour_src.index(src)
optimal_tour_src = optimal_tour_src[y:] + optimal_tour_src[:y]
optimal_tour_src.append(optimal_tour_src[0])
return optimal_tour_src, optimal_length
def greenTravel(adj_mat, src):
optimal_tour = []
n = len(adj_mat)
u = Node()
PQ = PriorityQueue()
optimal_length = 0
v = Node(level=0, path=[0])
min_length = float('inf')
v.bound = bound(adj_mat, v)
PQ.put(v)
while not PQ.empty():
v = PQ.get()
if v.bound < min_length:
u.level = v.level + 1
for i in filter(lambda x: x not in v.path, range(1, n)):
u.path = v.path[:]
u.path.append(i)
if u.level == n - 2:
l = set(range(1, n)) - set(u.path)
u.path.append(list(l)[0])
u.path.append(0)
_len = length(adj_mat, u)
if _len < min_length:
min_length = _len
optimal_length = _len
optimal_tour = u.path[:]
else:
u.bound = bound(adj_mat, u)
if u.bound < min_length:
PQ.put(u)
u = Node(level=u.level)
optimal_tour_src = optimal_tour
if src is not 1:
optimal_tour_src = optimal_tour[:-1]
y = optimal_tour_src.index(src)
optimal_tour_src = optimal_tour_src[y:] + optimal_tour_src[:y]
optimal_tour_src.append(optimal_tour_src[0])
return optimal_tour_src, optimal_length