# 自作ライブラリ
# https://github.com/takumi-okamoto/competitive-programming-public/tree/main/mylib

import sys
from collections import deque

# sys.setrecursionlimit(10**8)


def debug(*args):
    print(*args, file=sys.stderr)


def main():
    n, m = map(int, input().split())
    edges = [[] for _ in range(n)]
    for _ in range(m):
        u, v = map(int, input().split())
        u -= 1
        v -= 1
        edges[u].append(v)
        edges[v].append(u)

    INF = 10**18
    # INF = float("inf")
    dist = [[INF] * 5 for _ in range(n)]

    k = int(input())
    if k > 0:
        a = set(map(lambda x: int(x) - 1, input().split()))
    else:
        a = set()

    que = deque([(0, 0, 0)])  # dist, pos, count
    while que:
        d, p, ct = que.popleft()
        if dist[p][ct] <= d:
            continue
        dist[p][ct] = d

        for q in edges[p]:
            if q in a:
                if ct < 4:
                    que.append((d + 1, q, ct + 1))
            else:
                que.append((d + 1, q, 0))

    ans = min(dist[-1])
    # for i in range(n):
    #     debug(i + 1, dist[i])
    print(ans if ans < INF else -1)


if __name__ == "__main__":
    main()