Buggy python submission (verdict: Time Limit Exceeded):
import heapq
import itertools
N,M,R=map(int, raw_input().split())
r=map(int, raw_input().split())

cost=[ [ float("inf") for i in range(N+1)] for i in range(N+1) ]
nl=[ [] for i in range(N+1) ]

for i in range(M):
	A,B,C=map(int, raw_input().split())
	cost[A][B]=C
	cost[B][A]=C
	nl[A].append(B)
	nl[B].append(A)


for i in range(N+1): cost[i][i]=0


def Dij(start):

	#Initialize
	d=[float("inf") for i in range(N+1)]
	d[start]=0
	q=[]
	heapq.heappush(q,(0,start))
	
	while len(q)!=0:
		tmp=heapq.heappop(q)
		u=tmp[1]

		for v in nl[u]:
			alt=d[u]+cost[u][v]
			if d[v]>alt:
				d[v]=alt
				heapq.heappush(q,(alt,v))
	return d


l=list(itertools.permutations(r))

C=[[]]
for i in range(1,N+1):
	C.append(Dij(i))

ans=float("inf")


for i in l:
	dist=0
	for j in range(R):
		if j==0:
			prev=i[j]
			continue
		cur=i[j]
		dist+=C[prev][cur]
		prev=cur
	ans=min(ans,dist)

print ans




Fixed submission:
import heapq
import itertools
N,M,R=map(int, raw_input().split())
r=map(int, raw_input().split())

cost=[ [ float("inf") for i in range(N+1)] for i in range(N+1) ]
nl=[ [] for i in range(N+1) ]

for i in range(M):
	A,B,C=map(int, raw_input().split())
	cost[A][B]=C
	cost[B][A]=C
	nl[A].append(B)
	nl[B].append(A)


for i in range(N+1): cost[i][i]=0


def Dij(start):

	#Initialize
	d=[float("inf") for i in range(N+1)]
	d[start]=0
	q=[]
	heapq.heappush(q,(0,start))
	
	while len(q)!=0:
		tmp=heapq.heappop(q)
		u=tmp[1]

		for v in nl[u]:
			alt=d[u]+cost[u][v]
			if d[v]>alt:
				d[v]=alt
				heapq.heappush(q,(alt,v))
	return d


l=list(itertools.permutations(r))

C={}
for i in r:
	C[i]=Dij(i)


ans=float("inf")


for i in l:
	dist=0
	for j in range(R):
		if j==0:
			prev=i[j]
			continue
		cur=i[j]
		dist+=C[prev][cur]
		prev=cur
	ans=min(ans,dist)

print ans

Buggy python submission (verdict: Time Limit Exceeded):
import heapq
import itertools
N,M,R=map(int, raw_input().split())
r=map(int, raw_input().split())

cost=[ [ float("inf") for i in range(N+1)] for i in range(N+1) ]
nl=[ [] for i in range(N+1) ]

for i in range(M):
	A,B,C=map(int, raw_input().split())
	cost[A][B]=C
	cost[B][A]=C
	nl[A].append(B)
	nl[B].append(A)


for i in range(N+1): cost[i][i]=0


def Dij(start):

	#Initialize
	d=[float("inf") for i in range(N+1)]
	d[start]=0
	q=[]
	heapq.heappush(q,(0,start))
	
	while len(q)!=0:
		tmp=heapq.heappop(q)
		u=tmp[1]

		for v in nl[u]:
			alt=d[u]+cost[u][v]
			if d[v]>alt:
				d[v]=alt
				heapq.heappush(q,(alt,v))
	return d


l=list(itertools.permutations(r))


ans=float("inf")

for i in l:
	dist=0
	for j in range(R):
		if j==0:
			prev=i[j]
			continue
		cur=i[j]
		d=Dij(prev)
		dist+=d[cur]
		prev=cur
	ans=min(ans,dist)

print ans




Fixed submission:
import heapq
import itertools
N,M,R=map(int, raw_input().split())
r=map(int, raw_input().split())

cost=[ [ float("inf") for i in range(N+1)] for i in range(N+1) ]
nl=[ [] for i in range(N+1) ]

for i in range(M):
	A,B,C=map(int, raw_input().split())
	cost[A][B]=C
	cost[B][A]=C
	nl[A].append(B)
	nl[B].append(A)


for i in range(N+1): cost[i][i]=0


def Dij(start):

	#Initialize
	d=[float("inf") for i in range(N+1)]
	d[start]=0
	q=[]
	heapq.heappush(q,(0,start))
	
	while len(q)!=0:
		tmp=heapq.heappop(q)
		u=tmp[1]

		for v in nl[u]:
			alt=d[u]+cost[u][v]
			if d[v]>alt:
				d[v]=alt
				heapq.heappush(q,(alt,v))
	return d


l=list(itertools.permutations(r))

C={}
for i in r:
	C[i]=Dij(i)


ans=float("inf")


for i in l:
	dist=0
	for j in range(R):
		if j==0:
			prev=i[j]
			continue
		cur=i[j]
		dist+=C[prev][cur]
		prev=cur
	ans=min(ans,dist)

print ans

Buggy python submission (verdict: Time Limit Exceeded):
import itertools
N,M,R=map(int, raw_input().split())
r=map(int, raw_input().split())

dp=[ [ float("inf") for i in range(N+1)] for i in range(N+1) ]

for i in range(M):
	A,B,C=map(int, raw_input().split())
	dp[A][B]=C
	dp[B][A]=C

for i in range(N+1): dp[i][i]=0


for k in range(N+1):
	for x in range(N+1):
		for y in range(N+1):
			dp[x][y]=min( dp[x][y], dp[x][k]+dp[k][y] )


l=list(itertools.permutations(r))


ans=float("inf")

for i in l:
	dist=0
	for j in range(R):
		if j==0:
			prev=i[j]
			continue
		cur=i[j]
		dist+=dp[prev][cur]
		prev=cur
	ans=min(ans,dist)

print ans





Fixed submission:
import heapq
import itertools
N,M,R=map(int, raw_input().split())
r=map(int, raw_input().split())

cost=[ [ float("inf") for i in range(N+1)] for i in range(N+1) ]
nl=[ [] for i in range(N+1) ]

for i in range(M):
	A,B,C=map(int, raw_input().split())
	cost[A][B]=C
	cost[B][A]=C
	nl[A].append(B)
	nl[B].append(A)


for i in range(N+1): cost[i][i]=0


def Dij(start):

	#Initialize
	d=[float("inf") for i in range(N+1)]
	d[start]=0
	q=[]
	heapq.heappush(q,(0,start))
	
	while len(q)!=0:
		tmp=heapq.heappop(q)
		u=tmp[1]

		for v in nl[u]:
			alt=d[u]+cost[u][v]
			if d[v]>alt:
				d[v]=alt
				heapq.heappush(q,(alt,v))
	return d


l=list(itertools.permutations(r))

C={}
for i in r:
	C[i]=Dij(i)


ans=float("inf")


for i in l:
	dist=0
	for j in range(R):
		if j==0:
			prev=i[j]
			continue
		cur=i[j]
		dist+=C[prev][cur]
		prev=cur
	ans=min(ans,dist)

print ans