//g++ 2.cpp -std=c++14 -O2 -I .
#include <bits/stdc++.h>
using namespace std;

#include <atcoder/all>
using namespace atcoder;

using ll = long long;
using ld = long double;

using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vld = vector<ld>;
using vvld = vector<vld>;
using vst = vector<string>;
using vvst = vector<vst>;

#define fi first
#define se second
#define pb push_back
#define pq_big(T) priority_queue<T,vector<T>,less<T>>
#define pq_small(T) priority_queue<T,vector<T>,greater<T>>
#define all(a) a.begin(),a.end()
#define rep(i,start,end) for(ll i=start;i<(ll)(end);i++)
#define per(i,start,end) for(ll i=start;i>=(ll)(end);i--)
#define uniq(a) sort(all(a));a.erase(unique(all(a)),a.end())

// 距離 現在地 回収状況
using T = tuple<ll,int,int>;

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

  int n,m,k;
  cin>>n>>m>>k;

  vi need(m,-1);
  rep(i,0,k){
    int r;
    cin>>r;
    r--;
    need[r]=i;
  }

  // 行先 距離 index
  vector<vector<T>> g(n);
  rep(i,0,m){
    int a,b,c;
    cin>>a>>b>>c;
    a--;b--;
    g[a].emplace_back(b,c,i);
    g[b].emplace_back(a,c,i);
  }

  vvi dist(n,vi((1<<k),1e18));
  dist[0][0]=0;
  pq_small(T) que;
  que.push({0,0,0});

  while(!que.empty()){
    auto [d,now,road]=que.top();
    que.pop();

    if(d>dist[now][road]){
      continue;
    }

    for(auto [next,dis,id]:g[now]){
      int r=road;
      if(need[id]!=-1){
        r=(r|(1<<need[id]));
      }

      if(dist[next][r]>d+dis){
        dist[next][r]=d+dis;
        que.push({d+dis,next,r});
      }
    }
  }

  cout<<dist[n-1][(1<<k)-1]<<endl;
}