#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
constexpr int INF = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-8;
constexpr int MOD = 1000000007;
// constexpr int MOD = 998244353;
constexpr int DY[]{1, 0, -1, 0}, DX[]{0, -1, 0, 1};
constexpr int DY8[]{1, 1, 0, -1, -1, -1, 0, 1}, DX8[]{0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U> inline bool chmax(T& a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U> inline bool chmin(T& a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
  IOSetup() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    std::cout << fixed << setprecision(20);
  }
} iosetup;

template <typename CostType>
struct Edge {
  int src, dst; CostType cost;
  Edge(int src, int dst, CostType cost = 0) : src(src), dst(dst), cost(cost) {}
  inline bool operator<(const Edge &x) const {
    return cost != x.cost ? cost < x.cost : dst != x.dst ? dst < x.dst : src < x.src;
  }
  inline bool operator<=(const Edge &x) const { return !(x < *this); }
  inline bool operator>(const Edge &x) const { return x < *this; }
  inline bool operator>=(const Edge &x) const { return !(*this < x); }
};

int main() {
  int n, m, k; cin >> n >> m >> k;
  vector<int> r(m, -1);
  REP(i, k) {
    int ri; cin >> ri; --ri;
    r[ri] = i;
  }
  vector<int> c(m);
  vector<vector<Edge<int>>> graph(n);
  REP(i, m) {
    int a, b; cin >> a >> b >> c[i]; --a; --b;
    graph[a].emplace_back(a, b, i);
    graph[b].emplace_back(b, a, i);
  }
  vector dist(n, vector(1 << k, LINF));
  dist[0][0] = 0;
  priority_queue<pair<ll, pair<int, int>>, vector<pair<ll, pair<int, int>>>, greater<pair<ll, pair<int, int>>>> que;
  que.emplace(0, make_pair(0, 0));
  while (!que.empty()) {
    const auto [cost, ij] = que.top(); que.pop();
    const auto [i, j] = ij;
    if (cost > dist[i][j]) continue;
    for (const Edge<int>& e : graph[i]) {
      const int nj = j | (r[e.cost] == -1 ? 0 : 1 << r[e.cost]);
      if (chmin(dist[e.dst][nj], dist[i][j] + c[e.cost])) que.emplace(dist[e.dst][nj], make_pair(e.dst, nj));
    }
  }
  cout << dist[n - 1][(1 << k) - 1] << '\n';
  return 0;
}