import heapq
N,M = map(int,input().split())
G = [[[] for _ in range(5)] for _ in range(N+1)]
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 = [[INFTY for _ in range(5)] for _ in range(N+1)]
dist[1][0] = 0
que = [(0,1,0)]  # (距離,頂点)
while que:
    d,v,j = heapq.heappop(que)
    if dist[v][j]<d:continue
    for y,c in G[v][j]:
        if B[y]==1 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)