// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")


#include<bits/stdc++.h>
using namespace std;
using uint = unsigned int;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
template<class T> using V = vector<T>;
template<class T> using VV = V<V<T>>;
template<class T> using VVV = V<VV<T>>;
template<class T> using VVVV = VV<VV<T>>;
#define rep(i,n) for(ll i=0ll;(i)<(n);(i)++)
#define REP(i,a,n) for(ll i=(a);(i)<(n);(i)++)
#define rrep(i,n) for(ll i=(n)-1;(i)>=(0ll);(i)--)
#define RREP(i,a,n) for(ll i=(n)-1;(i)>=(a);(i)--)
const long long INF = (1LL << 60);
const long long mod99 = 998244353;
const long long mod107 = 1000000007;
const long long mod = mod99;
#define eb emplace_back
#define be(v) (v).begin(),(v).end()
#define all(v) (v).begin(),(v).end()
#define foa(i,v) for(auto& (i) : (v))
#define UQ(v) sort(be(v)), (v).erase(unique(be(v)), (v).end())
#define UQ2(v,cmp) sort(be(v)), (v).erase(unique(be(v),cmp), (v).end())
#define UQ3(v,cmp) sort(be(v),cmp), (v).erase(unique(be(v)), (v).end())
#define UQ4(v,cmp,cmp2) sort(be(v), cmp), (v).erase(unique(be(v),cmp2), (v).end())
#define LB(x,v) (lower_bound(be(v),(x))-(v).begin())
#define LB2(x,v,cmp) (lower_bound(be(v),(x),(cmp))-(v).begin())
#define UB(x,v) (upper_bound(be(v),(x))-(v).begin())
#define UB2(x,v,cmp) (upper_bound(be(v),(x),(cmp))-(v).begin())
#define dout()  cout << fixed << setprecision(20)
#define randinit() srand((unsigned)time(NULL))

template<class T, class U> bool chmin(T& t, const U& u) { if (t > u){ t = u; return 1;} return 0; }
template<class T, class U> bool chmax(T& t, const U& u) { if (t < u){ t = u; return 1;} return 0; }


ll Rnd(ll L=0, ll R=mod99){return rand()%(R-L)+L;}



void solve(){
    ll n,m;
    cin >> n >> m;
    V<ll> u, v;
    VV<ll> G(n);
    rep(i, m){
    	ll a,b;
    	cin >> a >> b;
    	a--;
    	b--;
    	u.eb(a);
    	v.eb(b);
    	G[a].eb(b);
    	G[b].eb(a);
    }
    V<ll> pos(n, 0);
    ll k;
    cin >> k;
    rep(i, k){
    	ll x;
    	cin >> x;
    	x--;
    	pos[x] = 1;
    }
    
    VV<ll> dist(5, V<ll>(n, INF));
    dist[0][0] = 0;
    queue<pair<ll,ll>> que;
    que.push({0, 0});
    while(!que.empty()){
    	auto[c, nd] = que.front();
    	que.pop();
    	for(auto nx:G[nd]){
    		ll nc = c*pos[nx] + pos[nx];
    		if(nc < 5 and chmin(dist[nc][nx], dist[c][nd] + 1)) que.push({nc, nx});
    	}
    }
    ll ans = INF;
    rep(i, 5) chmin(ans, dist[i][n-1]);
    if(ans == INF) ans = -1;
    cout << ans << '\n';
    
    
}

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int t=1;
    // cin >> t;
    rep(i,t) solve();
}