#include <bits/stdc++.h>
#include <atcoder/all>
#include <boost/multiprecision/cpp_dec_float.hpp>
#include <boost/multiprecision/cpp_int.hpp>
namespace mp = boost::multiprecision;
using Bint = mp::cpp_int;
using namespace std;
using namespace atcoder;
#define rep(i, n) for(int i=0;i<(n);++i)
#define rep1(i, n) for(int i=1;i<=(n);i++)
#define ll long long
using mint = modint998244353;
using P = pair<ll,ll>;
using lb = long double;
using T = tuple<ll, ll, ll>;
#ifdef LOCAL
#  include <debug_print.hpp>
#  define dbg(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define dbg(...) (static_cast<void>(0))
#endif

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);
    }
    int k;
    cin >> k;
    vector<int> a(n);
    rep(i,k) {
        int b;
        cin >> b;
        --b;
        a[b]++;
    }
    vector<vector<int>> dist(5, vector<int>(n,1e9));
    priority_queue<T, vector<T>, greater<T>> q;
    q.emplace(0,0,0);
    dist[0][0] = 0;
    while(!q.empty()) {
        auto [d1, d2, u] = q.top();q.pop();
        for(int v : g[u]) {
            if(a[v]) {
                if(d2+1==5) continue;
                if(d1+1<dist[d2+1][v]) {
                    dist[d2+1][v] = d1+1;
                    q.emplace(d1+1, d2+1, v);
                }
            }
            else{
                if(dist[0][v]>d1+1) {
                    dist[0][v] = d1+1;
                    q.emplace(d1+1,0,v); 
                }
            }
        }
    }
    int ans = 1e9;
    rep(i,5) ans = min(ans, dist[i][n-1]); 
    if(ans==1e9) ans=-1;
    cout<<ans<<endl;
    return 0;
}