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

template <class T> struct csr {
    using itr = typename std::vector<T>::iterator;
    struct Node {
        itr st, en;
        itr begin() { return st; }
        itr end() { return en; }
        int size() { return en - st; }
        T operator[](int p){ return st[p]; }
    };
    const int N;
    std::vector<int> start;
    std::vector<T> E;
    std::vector<std::pair<int,T>> edge;
    csr(int n) : N(n), start(n + 1) {}
    void add_edge(int u, T v){
        assert(0 <= u && u < N);
        start[u + 1]++;
        edge.emplace_back(u, v);
    }
    void build(){
        E.resize(edge.size());
        for(int i = 0; i < N; i++) start[i + 1] += start[i];
        auto cnt = start;
        for(auto [u, v] : edge) E[cnt[u]++] = v;
    }
    Node operator[](int p) {
        return Node{E.begin() + start[p], E.begin() + start[p + 1]};
    }
};

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, m;
    cin >> n >> m;
    csr<int> g(n);
    for(int i = 0; i < m; i++){
        int u, v;
        cin >> u >> v;
        u--, v--;
        g.add_edge(u, v);
        g.add_edge(v, u);
    }
    g.build();
    int k;
    cin >> k;
    vector<bool> tb(n);
    for(int i = 0; i < k; i++){
        int v;
        cin >> v;
        tb[v - 1] = true;
    }

    vector dp(n, vector<int>(5, 1 << 30));
    queue<pair<int,int>> que;
    dp[0][0] = 0;
    que.emplace(0, 0);
    while(!que.empty()){
        auto [v, s] = que.front();
        que.pop();
        for(auto u : g[v]){
            int ns = tb[u] ? s + 1 : 0;
            if(ns >= 5 || dp[v][s] + 1 >= dp[u][ns]) continue;
            dp[u][ns] = dp[v][s] + 1;
            que.emplace(u, ns);
        }
    }
    int ans = *min_element(dp[n - 1].begin(), dp[n - 1].end());
    if(ans >> 30) ans = -1;
    cout << ans << '\n';
}