//N連続岩井.
#include <bits/stdc++.h>
using namespace std;
#define int long long

int N,M;
int INF = 1e18;

signed main(){
  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<vector<int>> dist(5,vector<int>(N,INF));
  int K; cin>>K;
  vector<bool> A(N,false);
  for(int i = 0; i < K; i++){
  	int p; cin>>p; p--;
  	A[p] = true;
  }
  queue<pair<int,int>> Q;
  Q.push({0,0});
  dist[0][0] = 0;
  while(!Q.empty()){
  	int ren = Q.front().first;
  	int pos = Q.front().second;
  	Q.pop();
  	for(int i:G[pos]){
  		if(A[i]){
  			if(ren+1 >= 5) continue;
  			if(dist[ren+1][i] != INF) continue;
  			dist[ren+1][i] = dist[ren][pos] + 1;
  			Q.push({ren+1,i});
  		}
  		else{
  			if(dist[0][i] != INF) continue;
  			dist[0][i] = dist[ren][pos] + 1;
  			Q.push({0,i});
  		}
  	}
  }
  int ans = min({dist[0][N-1],dist[1][N-1],dist[2][N-1],dist[3][N-1],dist[4][N-1]});
  ans == INF ? cout << -1 << "\n" : cout << ans << "\n";
}