#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
#define OVERLOAD_REP(_1, _2, _3, name, ...) name
#define REP1(i, n) for (auto i = std::decay_t<decltype(n)>{}; (i) != (n); ++(i))
#define REP2(i, l, r) for (auto i = (l); (i) != (r); ++(i))
#define rep(...) OVERLOAD_REP(__VA_ARGS__, REP2, REP1)(__VA_ARGS__)
#define REP(i, l, r) rep(i, l, r+1)
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
using ll = long long;
using ld = long double;
using P = pair<ll,ll>;
struct Edge {
  int to; ll w;
};
using Graph = vector<vector<int> >;
//using Graph = vector<vector<Edge> >;
const ll INF = 2e18;
//const int INF = 2e9;
template<class T> using vc = vector<T>;
template<class T> using vv = vector<vector<T> >;
template<class T> using vvv = vector<vector<vector<T> > >;
template<class T> using pq = priority_queue<T>;
template<class T> using pq_g = priority_queue<T, vc<T>, greater<T> >;
template<class T> istream& operator>>(istream& i, vc<T>& v) { rep(j, 0, v.size()) i>>v[j]; return i; }
template<class T> ostream& operator<<(ostream& o, vc<T>& v) { rep(j, 0, v.size()) o<<v[j]<<" "; return o; }
template<class T> bool chmin(T& a, T b) {
  if(a > b) {
      a = b;
      return true;
  }
  return false;
}
template<class T> bool chmax(T& a, T b) {
  if(a < b) {
      a = b;
      return true;
  }
  return false;
}

int main() {
  // 高速化
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  // 小数点の出力桁数を指定
  cout << fixed << setprecision(10);
  // メイン
  int N, M;
  cin >> N >> M;
  Graph G(N);
  rep(i, 0, M) {
    int u, v;
    cin >> u >> v;
    u--, v--;
    G[u].push_back(v);
    G[v].push_back(u);
  }
  int K;
  cin >> K;
  set<int> a;
  rep(i, 0, K) {
    int A;
    cin >> A;
    a.insert(A-1);
  }

  queue<pair<int, int>> que;
  vv<int> dist(N, vc<int>(6, -1));
  que.push({0, 0});
  dist[0][0] = 0;
  while(!que.empty()) {
    auto [v, k] = que.front();
    que.pop();
    if(k >= 5) continue;
    for(int u : G[v]) {
      int nextk = 0;
      if(a.count(u)) nextk = k+1;
      if(dist[u][nextk]!=-1) continue;
      que.push({u, nextk});
      dist[u][nextk] = dist[v][k]+1;
    }
  }
  //rep(i, 0, N) { rep(j, 0, 6) cout << dist[i][j] << " "; cout << endl; }
  int ans = 1;
  rep(i, 0, 5) chmin(ans, -dist[N-1][i]);
  cout << -ans << endl;

  return 0;
}