#include <cstdio>
#include <vector>
#include <queue>
using namespace std;
const int NMAX = 2005;
const int INF = 0x7fffffff;
int cost[NMAX][20];
int dp[(1 << 16) + 5];
int a[NMAX];
struct Costuri {
  int nod, cost;
  bool operator < (const Costuri &other) const {
    return this->cost > other.cost;
  }
};
vector <Costuri> v[NMAX];
priority_queue <Costuri> pq;
void dijkstra(int x) {
  cost[a[x]][x] = 0;
  pq.push({a[x], 0});
  while(!pq.empty()) {
    Costuri nod = pq.top();
    pq.pop();
    if(nod.cost == cost[nod.nod][x]) {
      for(Costuri nnod : v[nod.nod]) {
        if(cost[nnod.nod][x] > nnod.cost + nod.cost) {
          cost[nnod.nod][x] = nnod.cost + nod.cost;
          pq.push({nnod.nod, nnod.cost + nod.cost});
        }
      }
    }
  }
}

int main() {
  int n, m, k;
  freopen("ubuntzei.in", "r", stdin);
  freopen("ubuntzei.out", "w", stdout);
  scanf("%d%d%d", &n, &m, &k);
  a[0] = 1;
  for(int i = 1; i <= k; i++) {
    scanf("%d", &a[i]);
  }
  for(int i = 1; i <= m; i++) {
    int x, y, z;
    scanf("%d%d%d", &x, &y, &z);
    v[x].push_back({y, z});
    v[y].push_back({x, z});
  }
  for(int i = 1; i <= n; i++) {
    for(int j = 0; j <= k; j++) {
      cost[i][j] = INF;
    }
  }
  for(int i = 0; i <= k; i++) {
    dijkstra(i);
  }
  int lim = 1 << k;
  for(int masca = 0; masca < lim; masca++) {
    dp[masca] = INF;
  }
  dp[0] = 0;
  for(int j = 0; j < k; j++) {
    dp[1 << j] = min(dp[1 << j], dp[0] + cost[a[j + 1]][0]);
    int val = dp[1 << j];
    val++;
  }
  for(int masca = 1; masca < lim; masca++) {
    for(int i = 0; i < k; i++) {
      if(!(masca & (1 << i))) {
        for(int j = 1; j <= k; j++) {
          if(masca & (1 << j)) {
            dp[(1 << i) + masca] = min(dp[(1 << i) + masca], dp[masca] + cost[a[i + 1]][j]);
          }
        }
      }
    }
  }
  int sol = INF;
  for(int i = 1; i <= k; i++) {
    sol = min(sol, dp[lim - 1] + cost[n][i]);
  }
  printf("%d\n", sol);
  return 0;
}