#include <bits/stdc++.h>

#include <atcoder/all>
using namespace std;
using i32 = int;
using u32 = unsigned int;
using i64 = long long;
using u64 = unsigned long long;
#define FAST_IO                \
  ios::sync_with_stdio(false); \
  cin.tie(0);
const i64 INF = 1001001001001001001;
using Modint = atcoder::static_modint<998244353>;

int main() {
  FAST_IO

  int N, M;
  cin >> N >> M;
  vector<int> U(M), V(M);
  for (int i = 0; i < M; i++) {
    cin >> U[i] >> V[i];
    U[i]--, V[i]--;
  }
  int K;
  cin >> K;
  vector<int> A(K);
  for (int i = 0; i < K; i++) {
    cin >> A[i];
    A[i]--;
  }

  set<int> st;
  for (int i = 0; i < K; i++) {
    st.insert(A[i]);
  }

  vector<vector<int>> G(N);
  for (int i = 0; i < M; i++) {
    G[U[i]].push_back(V[i]);
    G[V[i]].push_back(U[i]);
  }

  int m = 5;
  vector<vector<i64>> dist(N, vector<i64>(m, INF));
  using P = pair<i64, pair<int, int>>;
  priority_queue<P, vector<P>, greater<P>> pq;
  dist[0][0] = 0;
  pq.push({0, {0, 0}});

  while (!pq.empty()) {
    auto [d, p] = pq.top();
    pq.pop();
    auto [v, rem] = p;
    if (d > dist[v][rem]) continue;
    for (auto to : G[v]) {
      int nrem = st.contains(to) ? rem + 1 : 0;
      if (nrem < m && dist[to][nrem] > d + 1) {
        dist[to][nrem] = d + 1;
        pq.push({d + 1, {to, nrem}});
      }
    }
  }

  i64 ans = INF;
  for (int i = 0; i < m; i++) {
    ans = min(ans, dist[N - 1][i]);
  }
  if (ans == INF) ans = -1;
  cout << ans << endl;
}