import heapq as hq
import sys
input = sys.stdin.readline
INF = 10 ** 18

"""
Union-Find
from : https://github.com/customaddone/beginPython/blob/master/cgi-bin/library/unionfind/unionfind.py
ref : https://algo-logic.info/union-find-tree/
"""

class UnionFind():
	#Uni = UnionFind(n) のようにする
	def __init__(self, n):
		self.n = n
		self.parents = [-1] * n

	#xの親（親がいないときは自身の番号を返す）
	def find(self, x):
		if self.parents[x] < 0:
			return x
		else:
			self.parents[x] = self.find(self.parents[x])
			return self.parents[x]

	#xとyを関係付ける
	def union(self, x, y):
		x = self.find(x)
		y = self.find(y)

		if x == y:
			return

		if self.parents[x] > self.parents[y]:
			x, y = y, x
		# if x > y: # よりrootのインデックスが小さい方が親
			# x, y = y, x

		self.parents[x] += self.parents[y]
		self.parents[y] = x

	#xとyが同じ組に属するかどうか
	def same(self, x, y):
		return self.find(x) == self.find(y)

	#xが属する組の大きさ
	def size(self, x):
		return -self.parents[self.find(x)]

	#xが属する組の全要素をリストとして取得
	def members(self, x):
		root = self.find(x)
		return [i for i in range(self.n) if self.find(i) == root]

	#Union-Find木の根に当たる要素全てをリストとして取得
	def roots(self):
		return [i for i, x in enumerate(self.parents) if x < 0]

	#Union-Find木の根とそれに属する組の全要素
	def all_group_members(self):
		return {r: self.members(r) for r in self.roots()}

N,M,K = map(int, input().split())

if not(2 <= N <= 10 ** 4 and N - 1 <= M <= min(2 * 10 ** 4, N * (N - 1) // 2) and 1 <= K <= min(12, M)):
	exit(1)

R = [i - 1 for i in map(int, input().split())]
S = set(R)

if any(not(1 <= i + 1 <= M) for i in S):
	exit(1)
if not(len(S) == len(R) == K):
	exit(1)

edge = [[] for _ in [0] * M]
route = [[] for _ in [0] * N]
abst = set([])
uni = UnionFind(N)
for i in range(M):
	a,b,c = map(int, input().split())

	if((a,b) in abst):
		exit(1)
	abst.add((a,b));	abst.add((b,a))
	if not(1 <= a <= N and 1 <= b <= N and a != b and 1 <= c <= 10 ** 4):
		exit(1)

	a -= 1;	b -= 1

	uni.union(a,b)

	route[a].append((b,c))
	route[b].append((a,c))
	if(i in S):
		edge[i] = [a,b,c]

if not(uni.size(0) == N):
	exit(1)

def dijkstra(s,route):
	que = [(0,s)]
	dist = [INF] * N
	while(que):
		d,v = hq.heappop(que)
		if(dist[v] < INF):
			continue
		dist[v] = d
		for nv,nd in route[v]:
			hq.heappush(que,(d + nd, nv))
	return dist

dist = [[] for _ in [0] * N]
T = set([0,N - 1])
for i in S:
	T.add(edge[i][0])
	T.add(edge[i][1])
for i in T:
	dist[i] = dijkstra(i,route)

dp = [[[INF] * 2 for _ in [0] * K] for _ in [0] * (1 << K)]
for i in range(K):
	for j in range(2):
		dp[1 << i][i][j] = dist[0][edge[R[i]][j ^ 1]] + edge[R[i]][2]
for bit in range(1, 1 << K):
	for s in range(K):
		if not(bit & (1 << s)):
			continue
		for t in range(K):
			if(bit & (1 << t)):
				continue
			b = bit | (1 << t);	c = edge[R[t]][2]
			for x in range(2):
				for y in range(2):
					p = edge[R[s]][x];	q = edge[R[t]][y ^ 1]
					d = dp[bit][s][x] + dist[p][q] + c
					if(dp[b][t][y] > d):
						dp[b][t][y] = d

ans = INF
for i in range(K):
	for j in range(2):
		d = dp[-1][i][j] + dist[edge[R[i]][j]][N - 1]
		if(ans > d):
			ans = d
print(ans)