n,m,k=map(int,input().split())
r=[-1]*(1<<k)
for i,v in enumerate(list(map(int,input().split()))):
  r[v-1]=i
e=[[] for i in range(n)]
for i in range(m):
  a,b,c=map(int,input().split())
  a-=1
  b-=1
  e[a]+=[(i,b,c)]
  e[b]+=[(i,a,c)]
from heapq import heappush,heappop
X=10**10
v=[X]*(1<<k)*n
v[0*n+0]=0
q=[(0*n+0,0)]
while len(q)>0:
  sc,s=heappop(q)
  if sc>v[s]:
    continue
  sp,sy=divmod(s,n)
  for i,ty,tc in e[sy]:
    if r[i]!=-1:
      tp=sp|(1<<r[i])
    else:
      tp=sp
    t=tp*n+ty
    if v[t]>sc+tc:
      v[t]=sc+tc
      heappush(q,(v[t],t))
print(v[((1<<k)-1)*n+n-1])