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

int main(){
    int n,m;
    cin >> n >> m;

    vector<vector<int>>path (n,vector<int>(0));
    for(int i=0;i<m;i++){
        int x,y;
        cin >> x >> y;
        x--,y--;

        path[x].push_back(y);
        path[y].push_back(x);
    }

    vector<int>iwi (n,0);

    int k;
    cin >> k;
    for(int i=0;i<k;i++){
        int x;
        cin >> x;

        iwi[x-1] = 1;
    }
    
    int inf = (1<<30);
    vector<vector<int>>dp (5,vector<int>(n,inf));
    dp[0][0] = 0;
    
    queue<pair<int,pair<int,int>>>que;
    que.push({0,{0,0}});

    while(!que.empty()){
        auto [stp,hoge] = que.front();
        auto [app,pos] = hoge;
        que.pop();
        if(stp > dp[app][pos]) continue;

        for(auto nex:path[pos]){
            int np;
            if(iwi[nex] == 0) np = 0;
            else np = app + 1;

            if(np == 5) continue;

            if(dp[np][nex] > dp[app][pos] + 1){
                dp[np][nex] = dp[app][pos] + 1;
                que.push({dp[np][nex],{np,nex}});
            }
        }
    }

    int cnt = inf;
    for(int i=0;i<5;i++){
        cnt = min(cnt,dp[i][n-1]);
    }

    if(cnt == inf) cout << "-1" << endl;
    else cout << cnt << endl;   
    
}