/**
	author:  shobonvip
	created: 2025.09.07 09:11:53
**/

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

//* ATCODER
#include<atcoder/all>
using namespace atcoder;
typedef modint998244353 mint;
//*/

/* BOOST MULTIPRECISION
#include<boost/multiprecision/cpp_int.hpp>
using namespace boost::multiprecision;
//*/

typedef long long ll;

#define rep(i, s, n) for (int i = (int)(s); i < (int)(n); i++)
#define rrep(i, s, n) for (int i = (int)(n)-1; i >= (int)(s); i--)
#define all(v) v.begin(), v.end()

template <typename T> bool chmin(T &a, const T &b) {
	if (a <= b) return false;
	a = b;
	return true;
}

template <typename T> bool chmax(T &a, const T &b) {
	if (a >= b) return false;
	a = b;
	return true;
}

template <typename T> T max(vector<T> &a){
	assert(!a.empty());
	T ret = a[0];
	for (int i=0; i<(int)a.size(); i++) chmax(ret, a[i]);
	return ret;
}

template <typename T> T min(vector<T> &a){
	assert(!a.empty());
	T ret = a[0];
	for (int i=0; i<(int)a.size(); i++) chmin(ret, a[i]);
	return ret;
}

template <typename T> T sum(vector<T> &a){
	T ret = 0;
	for (int i=0; i<(int)a.size(); i++) ret += a[i];
	return ret;
}

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

	int n, m; cin >> n >> m;
	vector ikeru(n, vector<int>(0));
	rep(i,0,m) {
		int u, v; cin >> u >> v;
		u--; v--;
		ikeru[u].push_back(v);
		ikeru[v].push_back(u);
	}
	
	int k; cin >> k;
	vector<bool> has_iwai(n);
	rep(i,0,k) {
		int x; cin >> x;
		x--;
		has_iwai[x] = 1;
	}

	const int inf = 1e9;
	vector d(n, vector<int>(5, inf));
	d[0][0] = 0;
	deque<pair<int,int>> mada;
	mada.push_back(pair(0, 0));

	while(!mada.empty()) {
		auto [i, c] = mada.front();
		mada.pop_front();
		for (int j: ikeru[i]) {
			if (has_iwai[j]) {
				if (c == 4) {
					continue;
				}

				if (chmin(d[j][c+1], d[i][c] + 1)) {
					mada.push_back(pair(j, c+1));
				}
			}else{
				if (chmin(d[j][0], d[i][c] + 1)) {
					mada.push_back(pair(j, 0));
				}
			}
		}
	}

	int ans = min(d[n-1]);
	if (ans == inf) cout << -1 << '\n';
	else cout << ans << '\n';
}