#include <iostream>
#include <cstdio>
#include <vector>
#include <queue>
#define NMAX 2000
#define KMAX 15
#define DMAX 200000000
 
using namespace std;
 
struct elem {
  int nod, cost;
 
  elem(int nnod = 0, int ccost = 0) {
    nod = nnod, cost = ccost;
  }
};
 
int n, m, k;
int d[NMAX + 5];
int h[(1 << KMAX) + 5][KMAX + 5], dk[KMAX + 5][KMAX + 5];
vector<int> prt;
vector<elem> v[NMAX + 5];
priority_queue<elem, vector<elem>, greater<elem>> pq;
 
bool operator > (elem e1, elem e2) {
  if(e1.cost != e2.cost)
    return e1.cost > e2.cost;
  return e1.nod > e2.nod;
}
 
void dijkstra(int start) {
  elem crt, vec;
  for(int i = 1; i <= n; i++)
    d[i] = DMAX + 5;
 
  pq.push(elem(start, 0));
  while(!pq.empty()) {
    while(!pq.empty() && pq.top().cost >= d[pq.top().nod])
      pq.pop();
    if(pq.empty())
      break;
 
    crt = pq.top();
    pq.pop();
    d[crt.nod] = crt.cost;
 
    for(int i = 0; i < v[crt.nod].size(); i++) {
      vec = v[crt.nod][i];
      if(crt.cost + vec.cost < d[vec.nod])
        pq.push(elem(vec.nod, crt.cost + vec.cost));
    }
  }
}
 
void hamilton() {
  int pi, cnod, nbm;
 
  for(int bm = 1; bm < (1 << k); bm++)
    for(int i = 0; i < k; i++) {
      pi = 1 << i;
      cnod = prt[i];
      if(bm == pi)
        h[bm][i] = d[cnod];
      else if(bm & pi) {
        nbm = bm - pi;
        h[bm][i] = DMAX + 5;
        for(int j = 0; j < k; j++)
          if(j != i && ((1 << j) & nbm) != 0)
            h[bm][i] = min(h[bm][i], h[nbm][j] + dk[j][i]);
      }
    }
}
 
int main() {
  freopen("ubuntzei.in", "r", stdin);
  freopen("ubuntzei.out", "w", stdout);
  int x, y, z;
 
  scanf("%d %d", &n, &m);
  scanf("%d", &k);
  for(int i = 1; i <= k; i++) {
    scanf("%d", &x);
    prt.push_back(x);
  }
 
  for(int i = 1; i <= m; i++) {
    scanf("%d %d %d", &x, &y, &z);
    v[x].push_back(elem(y, z));
    v[y].push_back(elem(x, z));
  }
 
  for(int i = 0; i < k; i++) {
    dijkstra(prt[i]);
    for(int j = i + 1; j < k; j++)
      dk[j][i] = dk[i][j] = d[prt[j]];
  }
  dijkstra(1);
  hamilton();
  dijkstra(n);
 
  int ans = DMAX + 5, pk = 1 << k;
  for(int i = 0; i < k; i++)
    ans = min(ans, h[pk - 1][i] + d[prt[i]]);
  printf("%d", (k == 0) ? d[1] : ans);
 
  return 0;
}