import heapq
N,M = map(int,input().split())
G = {(i,j):[] for i in range(1,N+1) for j in range(5)}
for _ in range(M):
    u,v = map(int,input().split())
    for j in range(5):
        G[(u,j)].append((v,0))
        G[(v,j)].append((u,0))
        if j<4:
            G[(u,j)].append((v,j+1))
            G[(v,j)].append((u,j+1))
K = int(input())
B = [0]*(N+1)
if K>0:
    A = list(map(int,input().split()))
    for i in range(K):
        B[A[i]] = 1
INFTY = 10**6
dist = {(i,j):INFTY for i in range(1,N+1) for j in range(5)}
dist[(1,0)] = 0
que = [(0,(1,0))]  # (距離,頂点)
while que:
    d,x = heapq.heappop(que)
    v,j = x
    if dist[(v,j)]<d:continue
    for y,c in G[(v,j)]:
        if B[y]==1 and j<4 and c==j+1 and dist[(y,j+1)]>d+1:
            dist[(y,j+1)] = d+1
            heapq.heappush(que,(d+1,(y,j+1)))
        elif B[y]==0 and c==0 and dist[(y,0)]>d+1:
            dist[(y,0)] = d+1
            heapq.heappush(que,(d+1,(y,0)))
ans = min(dist[(N,j)] for j in range(5))
if ans>=INFTY:
    print(-1)
else:
    print(ans)