#include <bits/stdc++.h>
#define pi pair <int, int>
#define mp make_pair
#define f first
#define s second
#define inf (1<<26)
using namespace std;

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

int n, m, k, a[50], d[2005][2005], dp[(1<<16)][50];
bool city[2005];
vector < pair <int, int> > v[2005];
priority_queue <pi, vector<pi>, greater<pi> > pq;

void Dijkstra()
{
    for(int i = 0; i <= k; i++)
    {

      for(int j = i+1; j <= k+1; j++)
      {
          int x = a[j];
           pq.push(mp(0, a[i]));
          while(!pq.empty())
        {
            int nod = pq.top().s;
            int dist = pq.top().f;
            pq.pop();
            if(nod == x)
            {
                d[a[i]][nod] = dist;
                d[nod][a[i]] = dist;
                while(!pq.empty())pq.pop();
                break;
            }

            for(int j = 0; j < v[nod].size(); j++)
            {
                int child = v[nod][j].f;
                int price = v[nod][j].s;

                pq.push(mp(dist+price, child));

            }
        }
      }

    }
}

int main()
{
    fin >> n >> m;
    fin >> k;
    for(int i = 1; i <= k; i++)
    {
        int x;
        fin >> x;
        city[x] = 1;
        a[i] = x;
    }

    for(int i = 1; i <= m; i++)
    {
        int a, b, c;
        fin >> a >> b >> c;
        v[a].push_back(make_pair(b, c));
        v[b].push_back(make_pair(a, c));
    }

    a[0] = 1;
    city[n] = 1;
    a[k+1] = n;
    Dijkstra();

    for(int i = 0; i < (1<<k); i++)
        for(int j = 1; j <= 15; j++)
            dp[i][j] = inf;
    for(int i = 0; i < k; i++)
        dp[(1<<i)][i+1] = d[1][a[i+1]];

    for(int i = 1; i < (1<<k)-1; i++)
    {
        for(int j = 0; j < k; j++)
            if((1<<j)&i == 0)
                for(int p = 0; p < k; p++)
                    if((1<<p)&i == 1)
                        dp[i|(1<<j)][j+1] = min(dp[i|(1<<j)][j+1], dp[i][p+1]+d[a[p+1]][a[j+1]]);

    }
    int ans = inf;

    for(int i = 1; i <= k; i++)
        ans = min(ans, dp[(1<<k)-1][i]+d[a[i]][n]);
    fout << ans << '\n';



    return 0;
}