#include<iostream>
#include<vector>
#include<queue>
#include<tuple>
#include<algorithm>
using namespace std;
using ll = long long;
using P = pair<int, int>;
using tu = tuple<int, int, int>;

int main(void){
  int n, m; cin >> n >> m;
  vector<vector<int>> to(n);
  for(int i=0; i<m; i++){
    int u, v; cin >> u >> v; u--, v--;
    to[u].push_back(v);
    to[v].push_back(u);
  }
  vector<int> exi(n);
  int k; cin >> k;
  for(int i=0; i<k; i++){
    int a; cin >> a; a--;
    exi[a]++;
  }
  int inf=1e8;
  vector dist(n, vector<int>(5, 1e8));
  queue<tu> bfs;
  bfs.emplace(0, 0, 0);
  while(bfs.size()){
    auto [idx, d, cnt]=bfs.front(); bfs.pop();
    if(dist[idx][cnt]!=inf) continue;
    dist[idx][cnt]=d;
    for(auto p:to[idx]){
      if(exi[p]){
        if(cnt<4){
          bfs.emplace(p, d+1, cnt+1);
        }
      }
      else{
        bfs.emplace(p, d+1, 0);
      }
    }
  }
  int ans=1e8;
  for(int i=0; i<5; i++) ans=min(ans, dist[n-1][i]);
  if(ans==1e8) cout << -1 << endl;
  else cout << ans << endl;
  return 0;
}