#include <fstream>
#include <vector>
#include <set>
using namespace std;
ifstream fin("ubuntzei.in");
ofstream fout("ubuntzei.out");
const int oo = 2e7;
int n, m, k, i, x, d, y, c;
vector <vector <pair <int, int>>> v;
set <pair <int, int>> q;
vector <int> dist[16], cit;
void dijkstra (int x0, int target)
{
    for (i = 1; i <= n; i++)
        dist[target][i] = oo;
    dist[target][x0] = 0;
    q.insert(make_pair(0, x0));
    while (!q.empty())
    {
        x = (*q.begin()).second;
        q.erase(q.begin());
        for (i = 0; i < v[x].size(); i++)
        {
            y = v[x][i].first;
            c = v[x][i].second;
            if (dist[target][y] > dist[target][x] + c)
            {
                if (dist[target][y] != oo)
                    q.erase(q.find(make_pair(dist[target][y], y)));
                dist[target][y] = dist[target][x] + c;
                q.insert(make_pair(dist[target][y], y));
            }
        }
    }
}
int drumcalc(int lvl, int dr)
{
    int d = dr, mn = 2e7;
    for (int z = 1; z <= k; z++)
    {
        if (lvl < k && z != lvl) d = drumcalc(lvl+1, dist[lvl][cit[z]]+dr);
        else if (lvl == k) d = dist[lvl][n]+dr;
        mn = min(mn, d);
    }
    return mn;
}
int main()
{
    fin >> n >> m >> k; v.resize(n+1);
    for (i = 0; i <= k; i++)
        dist[i].resize(n+1);
    cit.push_back(1);
    for (i = 1; i <= k; i++)
    {
        fin >> x;
        cit.push_back(x);
    }
    for (i = 1; i <= m; i++)
    {
        fin >> x >> y >> c;
        v[x].push_back(make_pair(y, c));
        v[y].push_back(make_pair(x, c));
    }
    for (int j = 0; j <= k; j++)
        dijkstra(cit[j], j);
    d = drumcalc(0, 0);
    fout << d;
    return 0;
}