#include <fstream>
#include <queue>
#include <vector>

using namespace std;

using Pair = pair<int, int>;
using Matrix = vector<vector<int>>;

using Graph = vector<vector<Pair>>;
using Heap = priority_queue<Pair, vector<Pair>, greater<Pair>>;

constexpr int kInf = (1 << 30);

vector<int> Dijkstra(const Graph &g, int start)
{
  vector<int> dist(g.size(), kInf);
  Heap heap;

  dist[start] = 0;
  heap.push({0, start});

  while (!heap.empty()) {
    auto distance = heap.top().first;
    auto node = heap.top().second;
    heap.pop();

    if (distance > dist[node]) {
      continue;
    }

    for (const auto &e : g[node]) {
      auto next = e.first;
      auto new_distance = dist[node] + e.second;

      if (new_distance < dist[next]) {
        dist[next] = new_distance;
        heap.push({dist[next], next});
      }
    }
  }
  return dist;
}

Matrix GetDistances(const Graph &g, const vector<int> &cities)
{
  Matrix dist(cities.size());
  for (size_t i = 0; i < cities.size(); ++i) {
    dist[i] = Dijkstra(g, cities[i]);
  }
  return dist;
}

int CalcDist(const vector<int> &cities, const Matrix &dist, vector<int> ind)
{
  auto res = 0;
  auto last = cities[ind[0]];

  for (size_t i = 1; i < ind.size(); ++i) {
    auto city = cities[ind[i]];
    res += dist[last][city];
    last = city;
  }
  return res;
}

bool InVector(const vector<int> &vec, int size, int val)
{
  for (int i = 0; i < size; ++i) {
    if (vec[i] == val) {
      return true;
    }
  }
  return false;
}

int Back(const vector<int> &cities, const Matrix &dist)
{
  int n = cities.size() ;
  vector<int> st(n, 0);

  st[0] = 0;
  st.back() = n - 1;

  int res = kInf;
  int index = 1;

  while (index > 0) {
    do {
      st[index] += 1;
    } while (st[index] + 1 < n && InVector(st, index, st[index]));

    if (st[index] + 1 < n) {
      if (index + 1 == n - 1) {
        res = min(res, CalcDist(cities, dist, st));
      } else {
        st[++index] = 0;
      }
    } else {
      index -= 1;
    }
  }
  return res;
}

int Solve(const Graph &g, const vector<int> &cities)
{
  auto dist = GetDistances(g, cities);
  return Back(cities, dist);
}

int main()
{
  ifstream fin("ubuntzei.in");
  ofstream fout("ubuntzei.out");

  int nodes, edges;
  fin >> nodes >> edges;

  int ncities;
  fin >> ncities;

  vector<int> cities(ncities + 2);
  cities[0] = 0;
  cities[ncities + 1] = nodes - 1;

  for (int i = 1; i <= ncities; ++i) {
    fin >> cities[i];
    cities[i] -= 1;
  }

  Graph graph(nodes);
  for (int i = 0; i < edges; ++i) {
    int a, b, cost;
    fin >> a >> b >> cost;
    graph[a - 1].push_back({b - 1, cost});
    graph[b - 1].push_back({a - 1, cost});
  }

  auto res = Solve(graph, cities);
  fout << res << "\n";

  return 0;
}