#include <fstream>
#include <vector>
#include <set>
#define INF 1000000000

using namespace std;

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

int n,m,k,i,j,x,y,z,v[20],d[17][(1<<17)+5],dist[2005][2005];
vector< pair<int, int> > L[2005];
set< pair<int, int> > s;

int main()
{
    fin >> n >> m >> k;
    for (i=1; i<=k; i++)
        fin >> v[i];
    for (i=1; i<=m; i++)
    {
        fin >> x >> y >> z;
        L[x].push_back({y, z});
        L[y].push_back({x, z});
    }
    v[0] = 1; v[++k] = n;
    for (i=1; i<=k; i++)
        for (j=1; j<=n; j++)
            dist[v[i]][j] = INF;
    for (i=0; i<=k; i++)
    {
        dist[v[i]][v[i]] = 0;
        s.clear(); s.insert({0, v[i]});
        while (!s.empty())
        {
            int nod = s.begin()->second; s.erase(s.begin());
            for (j=0; j<L[nod].size(); j++)
            {
                int vecin = L[nod][j].first; int cost = L[nod][j].second;
                if (dist[v[i]][vecin] > dist[v[i]][nod]+cost)
                {
                    s.erase({dist[v[i]][vecin], vecin});
                    dist[v[i]][vecin] = dist[v[i]][nod]+cost;
                    dist[vecin][v[i]] = dist[v[i]][vecin];
                    s.insert({dist[v[i]][vecin], vecin});
                }
            }
        }
    }
    for (i=0; i<=k; i++)
        for (j=1; j<=(1<<k); j++)
            d[i][j] = INF;
    d[0][1] = 0;
    for (int mask=1; mask<(1<<k); mask++)
        for (i=0; i<k; i++)
            if (mask&(1<<i))
                for (j=0; j<k; j++)
                    if (i != j && (mask&(1<<j)))
                        d[i][mask] = min(d[i][mask], d[j][mask-(1<<i)]+dist[v[j]][v[i]]);
    int sol = INF;
    for (i=0; i<=k; i++)
        sol = min(sol, d[i][(1<<k)-1]+dist[v[i]][n]);
    fout << sol;
    return 0;
}