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

//pair<T, T>-> P<T>
template<class T> using P = pair<T, T>;
template<class T> struct item {T A, B, C;};

ll N, M, K;
vector<vector<ll>>G;

const ll INF = 1'000'000'000'000'000;
int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    cin>> N >> M;
    G.resize(N);
    for(int i=0; i<M; i++){
        ll u, v;
        cin >> u >> v;
        u--, v--;
        G[u].push_back(v);
        G[v].push_back(u);
    }
    cin>> K;
    vector<bool> iwai(100009);
    rep(i, 0, K) {
        ll a;
        cin >> a;
        a--; 
        iwai[a]=true;
    }
    
    queue<pair<ll, ll>> Q;
    Q.push(make_pair(0, 0));
    vector<vector<ll>> dist(N, vector<ll>(5, -1));
    dist[0][0]=0;
    while(!Q.empty())
    {
        auto [pos, cnt] = Q.front(); Q.pop();
        for(ll npos : G[pos])
        {
            ll ncnt=cnt;
            if(cnt==5 && iwai[npos])continue;
            if(iwai[npos]){
                ncnt++;
            }else ncnt=0;
            if(dist[npos][ncnt]!=-1)continue;
            Q.push({npos, ncnt});
            dist[npos][ncnt]=dist[pos][cnt]+1;
        }
    }
    ll ans=INF;
    for(int i=0; i<5; i++){
        if(dist[N-1][i]==-1)continue;
        ans = min(ans, dist[N-1][i]);
    }
    if(ans==INF)cout << -1 << endl;
    else cout << ans << endl;
    return 0;

}