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

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    ll N,M;
    cin>>N>>M;
    vector<vector<int>> G(N);
    for(int i=0;i<M;i++){
        int u,v;
        cin>>u>>v;
        u--;v--;
        G[u].push_back(v);
        G[v].push_back(u);
    } 
    vector<bool> I(N,0);
    int K;
    cin>>K;
    for(int i=0;i<K;i++){
        int a;
        cin>>a;
        I[a-1]=1;
    }
    queue<array<int,2>> Q;
    Q.push({0,0});
    vector<vector<ll>> D(N,vector<ll>(5,1e18));
    D[0][0]=0;
    vector<vector<bool>> seen(N,vector<bool>(5,0));
    while(!Q.empty()){
        auto [n,c]=Q.front();
        Q.pop();
        if(seen[n][c])continue;
        seen[n][c]=1;
        for(int v:G[n]){
            int nc=c;
            if(I[v])nc++;
            else nc=0;
            if(nc==5)continue;
            if(seen[v][nc])continue;
            if(D[v][nc]<=D[n][c]+1)continue;
            D[v][nc]=D[n][c]+1;
            Q.push({v,nc});
        }
    }
    cout<<(D[N-1][0]<1e17?D[N-1][0]:-1)<<"\n";
}