#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream f("ubuntzei.in");
ofstream g("ubuntzei.out");
vector <pair<int,int>> A[2001];
vector <int> a[16];
int ap[2001],c[16],n,m,k,x,y,j,i,z,Cost[16][16],C[1<<18+3][18],N,Sol;
const int INF = 0x3f3f3f3f;
void djikstra(int nod)
{
    priority_queue < pair <int,int>, vector < pair <int,int> >, greater < pair<int, int> > > Q;
    int dist[2001];
    fill(dist,dist+n+1,1<<30);
    dist[nod]=0;
    Q.push(make_pair(dist[nod],nod));
    while(!Q.empty())
    {
        int x=Q.top().second;
        Q.pop();
        for (int i=0; i<A[x].size(); i++)
        {
            int v=A[x][i].first, c=A[x][i].second;
            if (dist[v] > dist[x] + c)
            {
                dist[v]=dist[x]+c;
                Q.push(make_pair(dist[v],v));
            }
        }
    }
    for(int i=1;i<=n;i++)
        if(i!=nod&&ap[i])
            Cost[ap[i]-1][ap[nod]-1]=Cost[ap[nod]-1][ap[i]-1]=dist[i];


}
int main()
{
    f>>n>>m>>k;
    for(i=1;i<=k;i++)
    {
        f>>x;
        ap[x]=i+1;
        c[i+1]=x;
    }
    ap[1]=1;
    ap[n]=k+2;
    c[1]=1;
    c[k+2]=n;
    for(i=1;i<=m;i++)
    {
        f>>x>>y>>z;
        A[x].push_back(make_pair(y,z));
        A[y].push_back(make_pair(x,z));
    }
    for(i=1;i<=k+2;i++)
        djikstra(c[i]);
    N=k+2;
    for(i=0;i<N;i++)
        for(j=0;j<N;j++)
           if(i!=j) a[i].push_back(j);
    for (int i = 0; i < 1 << N; ++i)
        for (int j = 0; j < N; ++j) C[i][j] = INF;
    C[1][0] = 0;

    for (int i = 0; i < 1 << N; ++i)
        for (int j = 0; j < N; ++j)
            if (i & (1<<j))
                for (int k = 0; k < a[j].size(); ++k)
                    if (i & (1<<a[j][k]))
                        C[i][j] = min(C[i][j], C[i ^ (1<<j)][ a[j][k] ] + Cost[ a[j][k] ][j]);
    g<<C[(1<<N)-1][N-1];

    return 0;
}