#include <bits/stdc++.h>
#define INF 1000000001
#define L 2005
#define S 20
using namespace std;
ifstream fin("ubuntzei.in");
ofstream fout("ubuntzei.out");

int n, m, k;
vector <pair <int, int>> G[L];
vector <int> nodes;
int dist[L], cost[S][S];
bool vis[S];

void init_vis(){
  for (int i = 0; i < S; i++)
    vis[i] = false;
}

void dijkstra(int src){
  priority_queue <pair <int, int>> pq;
  int i, node, cost;
  for (i = 1; i <= n; i++)
    dist[i] = INF;
  dist[src] = 0;
  pq.push({-dist[src], src});
  while (!pq.empty()){
    cost = -pq.top().first;
    node = pq.top().second;
    pq.pop();
    if (cost == dist[node])
      for (auto it : G[node])
        if (cost + it.second < dist[it.first]){
          dist[it.first] = cost + it.second;
          pq.push({-dist[it.first], it.first});
        }
  }
  for (i = 1; i <= n; i++)
    if (dist[i] == INF)
      dist[i] = 0;
}

int main(){
  fin >> n >> m >> k;
  nodes.push_back(1);
  for (int i = 0; i < k; i++){
    int x;
    fin >> x;
    nodes.push_back(x);
  }
  nodes.push_back(n);
  for (int i = 0; i < m; i++){
    int a, b, c;
    fin >> a >> b >> c;
    G[a].push_back({b, c});
    G[b].push_back({a, c});
  }
  for (int i = 0; i < (int)nodes.size(); i++){
    dijkstra(nodes[i]);
    for (int j = 0; j < (int)nodes.size(); j++)
      cost[i][j] = dist[nodes[j]];
  }
  n = nodes.size();
  int ans = INF;
  int x, s;

  init_vis();
  x = s = 0;
  vis[x] = true;
  for (int i = 0; i < n - 2; i++){
    int mn = INF, p;
    for (int j = 1; j < n - 1; j++)
      if (!vis[j] && mn > cost[x][j]){
        mn = cost[x][j];
        p = j;
      }
    vis[p] = true;
    x = p;
    s += mn;
  }
  s += cost[x][n - 1];
  ans = min(ans, s);

  init_vis();
  s = 0;
  x = n - 1;
  vis[x] = true;
  for (int i = 0; i < n - 2; i++){
    int mn = INF, p;
    for (int j = 1; j < n - 1; j++)
      if (!vis[j] && mn > cost[x][j]){
        mn = cost[x][j];
        p = j;
      }
    vis[p] = true;
    x = p;
    s += mn;
  }
  s += cost[x][0];
  ans = min(ans, s);

  fout << ans << "\n";
  return 0;
}