G = read_file(filename)
start_time = time.time()
G.preprocess()
PQ = MaxHeap()
for i in range(G.N):
PQ.update(i, G.N * G.N)
S = set()
cur_val = G.N * G.N
used = set()
for curr_budget in range(budget):
while True:
cur, val, aux = PQ.pop()
if cur == -1: break
if cur in used: continue
new_val = G.avg_dist(S.union(set([cur])))
if cur_val - new_val == val:
S.add(cur)
cur_val = new_val
used.add(cur)
for y in G.G[cur]: used.add(y)
break
PQ.update(cur, cur_val - new_val)
end_time = time.time()
total_time = end_time - start_time
avg_dist = cur_val
#print S
print total_time, avg_dist
for i in range(G.N):
mg1 = G.avg_dist(set([i]))
prev_best = cur_best
if cur_best is not None:
mg2 = G.avg_dist(set([i]).union(set([cur_best])))
else:
mg2 = mg1
flag = 0
PQ.update((i, mg1, prev_best, mg2, flag), mg1)
if mg1 < cur_val:
cur_val = mg1
cur_best = i
# update
while len(seed) < budget:
val, dist = PQ.pop()
u = val[0]
mg1 = val[1]
prev_best = val[2]
mg2 = val[3]
flag = val[4]
if flag == len(seed):
seed = seed.union(set([u]))
last_seed = u
if cur_val != mg1:
print "ouch",u, len(seed)
continue
elif prev_best == last_seed:
mg1 = mg2
else:
withU = seed | set([u])
