#include <algorithm>
#include <atcoder/all>
#include <bitset>
#include <cassert>
#include <cmath>
#include <ctime>
#include <functional>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;
using namespace atcoder;
typedef long long ll;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repr(i, n) for (int i = (int)(n) - 1; i >= 0; i--)
#define repk(i, k, n) for (int i = k; i < (int)(n); i++)
#define all(v) v.begin(), v.end()
#define mod1 1000000007
#define mod2 998244353
#define mod3 100000007
#define vi vector<int>
#define vs vector<string>
#define vc vector<char>
#define vl vector<ll>
#define vb vector<bool>
#define vvi vector<vector<int>>
#define vvc vector<vector<char>>
#define vvl vector<vector<ll>>
#define vvb vector<vector<bool>>
#define vvvi vector<vector<vector<int>>>
#define vvvl vector<vector<vector<ll>>>
#define pii pair<int, int>
#define pil pair<int, ll>
#define pli pair<ll, int>
#define pll pair<ll, ll>
#define vpii vector<pair<int, int>>
#define vpll vector<pair<ll, ll>>
#define vvpii vector<vector<pair<int, int>>>
#define vvpll vector<vector<pair<ll, ll>>>

// using mint = modint998244353;

template <typename T>
void debug(T e) {
    cerr << e << endl;
}

template <typename T>
void debug(vector<T>& v) {
    rep(i, v.size()) { cerr << v[i] << " "; }
    cerr << endl;
}

template <typename T>
void debug(vector<vector<T>>& v) {
    rep(i, v.size()) {
        rep(j, v[i].size()) { cerr << v[i][j] << " "; }
        cerr << endl;
    }
}

template <typename T>
void debug(vector<pair<T, T>>& v) {
    rep(i, v.size()) { cerr << v[i].first << " " << v[i].second << endl; }
}

template <typename T>
void debug(set<T>& st) {
    for (auto itr = st.begin(); itr != st.end(); itr++) {
        cerr << *itr << " ";
    }
    cerr << endl;
}

template <typename T>
void debug(multiset<T>& ms) {
    for (auto itr = ms.begin(); itr != ms.end(); itr++) {
        cerr << *itr << " ";
    }
    cerr << endl;
}

template <typename T>
void debug(map<T, T>& mp) {
    for (auto itr = mp.begin(); itr != mp.end(); itr++) {
        cerr << itr->first << " " << itr->second << endl;
    }
}

void debug_out() { cerr << endl; }

template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
    cerr << H << " ";
    debug_out(T...);
}

using mint = modint1000000007;

void debug_mint1(vector<mint>& vec) {
    for (int i = 0; i < vec.size(); i++) {
        cerr << vec[i].val() << " ";
    }
    cerr << endl;
}

void debug_mint2(vector<vector<mint>>& vec) {
    for (int i = 0; i < vec.size(); i++) {
        for (int j = 0; j < vec[i].size(); j++) {
            cerr << vec[i][j].val() << " ";
        }
        cerr << endl;
    }
}

int main() {
    ll N, M;
    cin >> N >> M;
    vector<ll> U(M);
    vector<ll> V(M);
    for (ll i = 0; i < M; i++) {
        cin >> U[i] >> V[i];
        U[i]--;
        V[i]--;
    }
    ll K;
    cin >> K;
    vector<ll> A(K);
    for (ll i = 0; i < K; i++) {
        cin >> A[i];
    }
    vector<bool> has(N, false);
    for (ll i = 0; i < K; i++) {
        has[A[i] - 1] = true;
    }

    ll INF = 100000000000023;
    vector<vector<ll>> dist(N, vector<ll>(5, INF));
    dist[0][0] = 0;

    queue<pll> que;
    que.push(make_pair(0, 0));

    vector graph(N, vector<ll>(0));
    for (ll i = 0; i < M; i++) {
        graph[U[i]].push_back(V[i]);
        graph[V[i]].push_back(U[i]);
    }

    while (que.size()) {
        pll p = que.front();
        que.pop();
        for (ll x : graph[p.first]) {
            if (has[x]) {
                if (p.second == 4) {
                    continue;
                }
                if (dist[x][p.second + 1] == INF) {
                    dist[x][p.second + 1] = dist[p.first][p.second] + 1;
                    que.push(make_pair(x, p.second + 1));
                }
            } else {
                if (dist[x][0] == INF) {
                    dist[x][0] = dist[p.first][p.second] + 1;
                    que.push(make_pair(x, 0));
                }
            }
        }
    }
    ll ans = INF;
    for (ll i = 0; i < 5; i++) {
        ans = min(ans, dist[N - 1][i]);
    }
    // debug(dist);
    cout << (ans == INF ? -1 : ans) << endl;
}