N,M=map(int,input().split())
G=[[] for i in range(N)]
for i in range(M):
  a,b=map(int,input().split())
  G[a-1].append(b-1)
  G[b-1].append(a-1)
K=int(input())
u=[False]*N
if K>0:
  B=list(map(int,input().split()))
for i in range(K):
  u[B[i]-1]=True
dp=[[10**10]*5 for i in range(N)]
dp[0][0]=0
from heapq import heappush,heappop
S=[]
heappush(S,0)
kaku=[[False]*5 for i in range(N)]
while S:
  w=heappop(S)
  cost=w//(10**6)
  w-=cost*10**6
  pos=w//5
  t=w%5
  if kaku[pos][t]==True:
    continue
  kaku[pos][t]=True
  for y in G[pos]:
    t2=t
    if u[y]==True:
      t2+=1
    else:
      t2=0
    if t2<5:
      if dp[y][t2]>dp[pos][t]+1:
        dp[y][t2]=dp[pos][t]+1
        heappush(S,(dp[y][t2])*10**6+y*5+t2)
result=dp[N-1][0]
if result>10**9:
  result=-1
print(result)