#ifndef ONLINE_JUDGE
#define _GLIBCXX_DEBUG //[]で配列外参照をするとエラーにしてくれる。上下のやつがないとTLEになるので注意 ABC311Eのサンプル4みたいなデバック中のTLEは防げないので注意
#endif
#include <bits/stdc++.h>
#include <algorithm>
#include <cmath> // M_PIを使用するため
using namespace std;

using ll = long long;
using ld = long double;
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
#define rrep(i, n) for (ll i = (ll)n - 1; i >= 0; --i)

const ll INF = (1LL << 62);
const ll null = -1LL;
template <typename T>
using vc = vector<T>; // prioriy_queueに必要なのでここにこれ書いてます
template <typename T>
using vv = vc<vc<T>>;
template <typename T>
using vvv = vv<vc<T>>;
using vl = vc<ll>;
using vvl = vv<ll>;
using vvvl = vv<vl>;
using vvvvl = vv<vvl>;
using vs = vc<string>;
using vvs = vv<string>;
using vb = vc<bool>;
using vvb = vc<vb>;
using P = pair<ll, ll>;

template <class T>
istream &operator>>(istream &i, vc<T> &v)
{
    rep(j, size(v)) i >> v[j];
    return i;
}
// それぞれ「下，上，右，左」に対応
int dx[4] = {1, -1, 0, 0};
int dy[4] = {0, 0, 1, -1};

#define nall(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()

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;
}

#define pb push_back
#define eb emplace_back
#define em emplace
#define pob pop_back
#define next_p(v) next_permutation(v.begin(), v.end())

void solve()
{
    ll n, m; cin >> n >> m;
    vvl G(n);
    rep(_,m) {
        ll u, v; cin >> u >> v;
        --u, --v;
        G[u].pb(v); G[v].pb(u);   
    }
    ll k; cin >> k;
    vb isyiwiy(n,false);

    rep(_,k) {
        ll pos; cin >> pos;
        isyiwiy[pos-1] = true;
    }

    vvl dist(n,vl(5,INF));
    dist[0][0] = 0;
    queue<P> q;
    q.em(0,0);

    while (q.size()) {
        auto [v,md] = q.front(); q.pop();
        for (ll nv : G[v]) {
            ll nmd = md;
            if (isyiwiy[nv]) nmd++;
            else nmd = 0;
            
            if (nmd >= 5) continue;
            if (dist[nv][nmd] != INF) continue;
            dist[nv][nmd] = dist[v][md] + 1ll;
            q.em(nv,nmd);
        }
    }

    ll ans = INF;
    rep(i,5) chmin(ans,dist[n-1][i]);
    cout << (ans < INF? ans : -1) << endl;


    
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    ll testcases = 1ll;
    // cin >> testcases;
    rep(_, testcases) solve();

    return 0;
}