#include <fstream>
#include <vector>
#include <queue>
#include <algorithm>
#define NMax 2002
#define INF 1<<30
using namespace std;
ifstream fin("ubuntzei.in");
ofstream fout("ubuntzei.out");
std::vector<int> G[NMax],C[NMax],A;
std::queue< std::pair<int,int> > coada;
int n,m,k,x,y,cost,d[NMax],CF[20][NMax],B[NMax],Maxim;
void dijkstra(int x0)
{
    fill(d+1,d+n+1,INF);
    d[x0] = 0;
    coada.push(std::make_pair(0,x0));
    while(coada.empty()==0)
    {
        int val = (coada.front()).first;
        int nod = (coada.front()).second;
        coada.pop();
        for(int i=0;i<G[nod].size();++i)
        {
            if(d[G[nod][i]] > val + C[nod][i])
            {
                d[G[nod][i]] = val + C[nod][i];
                coada.push(std::make_pair(d[G[nod][i]],G[nod][i]));
            }
        }
    }
}
int main()
{
    Maxim = INF;
    fin>>n>>m>>k;
    for(int i=1;i<=k;++i)
    {
        fin>>x;
        A.push_back(x);
    }
    for(int i=1;i<=m;++i)
    {
        fin>>x>>y>>cost;
        G[x].push_back(y);
        G[y].push_back(x);
        C[x].push_back(cost);
        C[y].push_back(cost);
    }
    if(k==0)
    {
        dijkstra(1);
        fout<<d[n];
    }
    else
    {
        sort(A.begin(),A.end());
        for(int i=0;i<A.size();++i)
        {
            B[A[i]] = i;
            dijkstra(A[i]);
            for(int j=1;j<=n;++j)
            {
                CF[i][j] = d[j];
            }
        }
        do
        {
            int contor = 0;
            for(int i=0;i<A.size();++i)
            {
                if(i==0)contor+=CF[B[A[i]]][1];
                else contor+=CF[B[A[i]]][A[i-1]];
            }
            contor+=CF[B[A[A.size()-1]]][n];
            if(contor<Maxim)Maxim = contor;
        }while(next_permutation(A.begin(),A.end()));
        fout<<Maxim;
    }
    return 0;
}