#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define srep(i,l,r) for(ll i=l;i<=r;i++)
#define irep(i,r,l) for(ll i=r;i>=l;i--)
using ll = long long;
using ld = long double;
constexpr ll mod = 998244353ll;
#define vout(v) for(auto i :v) cout<<i<<" ";
#define INF 9223300000000000000ll
#define Winf 5e12
#define nl "\n"
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define vl vector<ll>
#define pb push_back

#define vc vector<char>
#define vb vector<bool>
#define uniq(x) sort((x).begin(),(x).end());(x).erase(unique((x).begin(),(x).end()),(x).end())
#define eb emplace_back



void no(void) { cout<<"No"<<nl;}
void yes(void) {cout<<"Yes"<<nl;}
void yn(bool a) {
    cout<<(a ? "Yes":"No")<<nl;
}


vector<ll> dx={-1,0,1,0,1,1,-1,-1};
vector<ll> dy={0,-1,0,1,-1,1,-1,1};

bool isin(ll i,ll j,ll h,ll w) {
    if(i<0 || i>=h || j<0 || j>=w) return false;
    return true;
}

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


template<class T>T vefSYS_perf_event_open(const vector<T>&v){return fSYS_perf_event_open_element(all(v));}
template<class T>T vecmin(const vector<T>&v){return *min_element(all(v));}

ll safemod(ll num,ll rule) {
    return (num%rule+rule)%rule;
}
//alias ojb='oj-bundle -I /home/leal/beginner/atc/library'
ll sum(vector<ll> &a) {
    return accumulate(all(a),0ll);
}

int main() {
    ll n,m; cin>>n>>m;
    vector<vector<ll>> g(n);
    vector<pair<ll,ll>> e(m);
    rep(i,m) {
        cin>>e[i].first>>e[i].second;
        e[i].first--;
        e[i].second--;
    }
    vector<ll> yiwiy(n,0);
    ll k; cin>>k;
    rep(i,k) {
        ll a; cin>>a; a--;
        yiwiy[a]=1;
    }
    for(auto [u,v]:e) {
        g[u].pb(v);
        g[v].pb(u);
    }
    vector<array<ll,6>> dist(n);
    rep(i,n) srep(c,0,5) dist[i][c]=INF;
    queue<pair<ll,ll>> que;
    dist[0][0]=0;
    que.emplace(0,0);

    while(!que.empty()) {
        auto [v,c]=que.front();
        que.pop();
        int d=dist[v][c];
        for(int to : g[v]){
            int nc=c+(yiwiy[to] ? 1 : 0);
            if(!yiwiy[to]) nc=0;
            if(nc>=5) continue;
            if(dist[to][nc]==INF){
                dist[to][nc]=d+1;
                que.emplace(to,nc);
            }
        }
    }
    ll ans=INF;
    srep(i,0,4) chmin(ans,dist[n-1][i]);
    cout<<(ans!=INF ? ans:-1)<<nl;
}