//#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
#define all(a) (a).begin(), (a).end()
using ll = long long;
const ll INF32 = 2e9;
const ll INF64 = 4e18;

void printYN(bool ok){
    if(ok)cout << "Yes" << endl;
    else cout << "No" << endl;
    return;
}

int main() {
    int N, M;
    cin >> N >> M;
    vector<vector<int>> G(N);
    rep(i, M){
        int u, v;
        cin >> u >> v;
        u--; v--;
        G[u].push_back(v);
        G[v].push_back(u);
    }
    vector<bool> IWAI(N);
    int K;
    cin >> K;
    rep(i, K){
        int ai;
        cin >> ai;
        ai--;
        IWAI[ai] = true;
    }
    vector<vector<int>> dist(5, vector<int>(N, INF32));
    dist[0][0] = 0;
    queue<pair<int, int>> q;
    q.push({0,0});
    while(!q.empty()){
        auto [i, j] = q.front();
        q.pop();
        for(auto p: G[j]){
            int nxi;
            if(IWAI[p])nxi = i+1;
            else nxi = 0;
            if(nxi>=5)continue;
            if(dist[nxi][p]!=INF32)continue;
            dist[nxi][p] = dist[i][j] +1;
            q.push({nxi, p});
        }
    }
    int ans = INF32;
    rep(i, 5)ans = min(ans, dist[i][N-1]);
    if(ans!=INF32)cout << ans << endl;
    else cout << -1 << endl;
    return 0;
}