#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
using ll = long long;

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

  ll n, m; cin >> n >> m;
  vector<vector<ll>> G(n);
  rep(i, m) {
    ll u, v; cin >> u >> v;
    --u; --v;
    G[u].push_back(v);
    G[v].push_back(u);
  }

  ll k; cin >> k;
  set<ll> bad;
  rep(i, k) {
    ll a; cin >> a;
    bad.insert(a - 1);
  }

  vector<vector<array<ll,3>>> D(n, vector<array<ll,3>>(5, {LLONG_MAX, -1, -1}));
  D[0][0] = {0, -1, -1};

  queue<pair<ll,ll>> q;
  q.push({0, 0});

  while (!q.empty()) {
    auto [v, b] = q.front(); q.pop();
    ll dist = D[v][b][0];
    for (ll to : G[v]) {
      if (bad.count(to)) {
        if (b < 4 && D[to][b+1][0] > dist + 1) {
          D[to][b+1] = {dist + 1, v, b};
          q.push({to, b+1});
        }
      } else {
        if (D[to][0][0] > dist + 1) {
          D[to][0] = {dist + 1, v, b};
          q.push({to, 0});
        }
      }
    }
  }

  ll ans = LLONG_MAX;
  for (int b = 0; b < 5; ++b) ans = min(ans, D[n-1][b][0]);
  cout << (ans == LLONG_MAX ? -1 : ans) << '\n';
}