#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#ifdef LOCAL
#include <debug.hpp>
#else
#define debug(...)
#endif

constexpr int INF = (1 << 30) - 1;

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(20);
    int N, M;
    cin >> N >> M;
    vector<vector<int>> G(N);
    for (int i = 0; i < M; i++) {
        int U, V;
        cin >> U >> V, U--, V--;
        G[U].emplace_back(V);
        G[V].emplace_back(U);
    }
    int K;
    cin >> K;
    vector<int> isiwi(N);
    for (int i = 0; i < K; i++) {
        int A;
        cin >> A, A--;
        isiwi[A] = true;
    }

    vector dist(5, vector<int>(N, INF));
    queue<pair<int, int>> que;
    dist[0][0] = 0;
    que.emplace(0, 0);

    while (!que.empty()) {
        auto [iwi, v] = que.front();
        que.pop();
        for (auto u : G[v]) {
            int niwi = isiwi[u] ? iwi + 1 : 0;
            if (niwi >= 5) continue;
            if (dist[niwi][u] != INF) continue;
            dist[niwi][u] = dist[iwi][v] + 1;
            que.emplace(niwi, u);
        }
    }

    int ans = INF;
    for (int i = 0; i < 5; i++) {
        ans = min(ans, dist[i][N - 1]);
    }

    cout << (ans == INF ? -1 : ans) << "\n";
}