#include <bits/stdc++.h>
using namespace std;

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

vector<pair<int, int>> L[2005];
bitset<2005> v;
int d[2005];
priority_queue<pair<int, int>> q;
int n, m, k;
int localitate[2005];
int Total;

void Dijkstra(int k)
{
    int i, x;
    d[k] = 0;
    q.push({0, k});
    while(!q.empty())
    {
        k = q.top().second;
        q.pop();
        for(auto w : L[k])
        {
            int dis = w.first;
            int nod = w.second;
            if(d[nod] > d[k] + dis)
            {
                d[nod] = d[k] + dis;
                q.push({-d[nod], nod});
            }
        }
    }
}

int main()
{
    int i, x, y, c;
    fin >> n >> m;
    fin >> k;
    for(i=1; i<=k; i++)
        fin >> localitate[i];
    for(i=1; i<=m; i++)
    {
        fin >> x >> y >> c;
        L[x].push_back({c, y});
        L[y].push_back({c, x});
    }
    for(i=1; i<=n; i++)
        d[i] = 2e9;
    int vecini = k;
    int p = 1;
    while(vecini >= 1)
    {
        Dijkstra(p);
        int mini = 2e9;
        for(i=1; i<=k; i++)
            if(v[localitate[i]] == 0 && d[localitate[i]] < mini)
            {
                mini = d[localitate[i]];
                p = localitate[i];
            }
        v[p] = 1;
        Total += mini;
        for(i=1; i<=n; i++)
            d[i] = 2e9;
        //fout << p << ' ' << Total << " ";
        vecini--;
    }
    Dijkstra(p);
    fout << d[n] + Total << " ";
    fin.close();
    fout.close();
    return 0;
}