#include<bits/stdc++.h>
#include<atcoder/all>
#define rep(i,j,n) for(ll i=j;i<(ll)(n);i++)
#define rrep(i,j,n)  for(ll i=j;i>=n;i--)
#define all(x) (x).begin(),(x).end()
#define m0(x) memset(x,0,sizeof(x))
#define pb emplace_back
#define mp make_pair
#define perm(c) sort(all(c)); for(bool c##p=1;c##p;c##p=next_permutation(all(c)))
#define UNIQUE(v) sort(v.begin(),v.end()); v.erase(unique(v.begin(),v.end()),v.end())

using namespace std;
using namespace atcoder;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
template<class T> bool chmax(T &a, const T &b){if(a<b) {a=b;return 1;}return 0;}
template<class T> bool chmin(T &a, const T &b){if(a>b) {a=b;return 1;}return 0;}
const ll LINF = 1LL << 60LL;
const int IINF = (1 << 30) - 1;

namespace detail {
  template <typename Tp, size_t Nb>
  auto make_v(std::vector<size_t>& sizes, Tp const& x) {
    if constexpr (Nb == 1) {
      return std::vector(sizes[0], x);
    } else {
      size_t size = sizes[Nb-1];
      sizes.pop_back();
      return std::vector(size, make_v<Tp, Nb-1>(sizes, x));
    }
  }
}  // detail::

template <typename Tp, size_t Nb>
auto make_v(size_t const(&sizes)[Nb], Tp const& x = Tp()) {
  std::vector<size_t> s(Nb);
  for (size_t i = 0; i < Nb; ++i) s[i] = sizes[Nb-i-1];
  return detail::make_v<Tp, Nb>(s, x);
}
ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}
void yn(bool ok){
    if(ok) cout << "Yes\n";
    else cout << "No\n";
}

void solve(){
    ll n,m; cin >> n >> m;
    vector<vector<ll>> graph(n);
    rep(i,0,m){
        ll u,v; cin >> u >> v;
        u--;v--;
        graph[u].pb(v);
        graph[v].pb(u);
    }
    ll k; cin >> k;
    vector<ll> stone(n,0);
    rep(i,0,k){
        ll v; cin >> v;
        stone[v-1] = 1;
    }
    auto memo = make_v({n,5},LINF);
    queue<tuple<ll,ll,ll>> que;
    que.push({0,0,0});
    while(!que.empty()){
        auto [d,v,s] = que.front();
        que.pop();
        if(d >= memo[v][s]) continue;
        memo[v][s] = d;
        for(auto u : graph[v]){
            if(stone[u]){
                if(s < 4) que.push({d+1,u,s+1});
            }
            else{
                que.push({d+1,u,0});
            }
        }
    }
    ll ans = LINF;
    rep(i,0,4) chmin(ans,memo[n-1][i]);
    if(ans == LINF) cout << "-1\n";
    else cout << ans << "\n";
}

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(20);

    ll T;
    T = 1;
    /*
       cin >> T;
       */
    while(T--) solve();
}